Tomato leaves curling is one of the most alarming-looking tomato problems, but in UK gardens it is usually one of the least serious. The great majority of leaf curl is physiological, meaning it is the plant reacting to its conditions rather than any disease, most often to swings in temperature, too much or too little water, wind, or hard pruning combined with heavy feeding. This kind of curl typically starts on the lower, older leaves, which cup or roll inwards and feel slightly leathery while staying green, and it usually rights itself once conditions settle, without affecting your crop. The much rarer and more serious causes are weedkiller drift and virus, which look different and need a different response. So the first job is not to panic, but to look closely and work out which kind of curl you are actually seeing, because the common one is nothing to worry about.

I have grown tomatoes for over twenty years on my Oxfordshire plot, and my greenhouse plants curl their lower leaves almost every year when we get a run of cold nights after warm days. The first time it happened I was convinced I had some dreadful disease, and I nearly pulled the plants. In fact they cropped perfectly well. Let me walk you through the causes, how to tell them apart, and what, if anything, you actually need to do.

First, Look Closely at the Curl

Diagnosing tomato leaves curling is all about detective work, and a few quick observations tell you most of what you need to know. Ask yourself: which leaves are affected, the old lower ones or the new top growth? Which way do they curl, upward and inward, or downward and twisted? And is anything else wrong, like distorted new shoots, odd colours, or malformed fruit? The answers point straight at the cause, because the harmless physiological curl and the serious causes affect different leaves in different ways.

As a rule of thumb, curl that starts on the lower, older leaves and leaves the plant otherwise healthy is almost always the harmless physiological kind. Curl or distortion on the new top growth, especially with twisting or strange fruit, is the warning sign that points to weedkiller or virus. Keep those two patterns in mind as you read the causes below, since telling them apart is the whole game. It fits the same diagnostic approach as the wider common tomato problems guide.

Cause 1: Temperature Swings (Most Common)

By far the most common cause of tomato leaf curl in the UK is fluctuating temperature, particularly warm days followed by cold nights. The plant cannot process the sugars it made during the day when the night turns too cold, and the leaves curl in response. This is exactly why it shows up so often in home greenhouses and polytunnels, which heat up dramatically by day and cool sharply at night, far more than a large commercial glasshouse would. It is the classic early-summer greenhouse tomato complaint.

The good news, and I cannot stress this enough, is that this kind of curl is harmless. The leaves stay green, the plant grows and crops normally, and it usually sorts itself out as the nights warm up in high summer. There is nothing you need to do beyond ventilating the greenhouse well to even out the temperature swings. The RHS advice on tomato leaf problems confirms this temperature-driven curl does not seem to cause any real loss of crop, so do not let it worry you.

Cause 2: Watering and Stress

The next most common cause is water stress, and it works both ways. Too little water makes leaves curl to reduce their surface area and save moisture, a sensible survival response, while too much water and soggy roots can also trigger curling, since tomatoes hate sitting wet. Other stresses do the same thing: strong wind on unsupported plants, root disturbance from hoeing too close, transplant shock, and severe pruning, especially when combined with heavy nitrogen feeding, can all make leaves roll.

The fix here is simply to steady the conditions. Water consistently and evenly so the plant is neither parched nor waterlogged, as in how often to water, support and shelter plants from wind, avoid disturbing the roots, and do not go mad removing side shoots and leaves all at once. Ease off high-nitrogen feed too, feeding sensibly as in feeding vegetables properly. Remove side shoots gradually, as covered in removing side shoots, rather than stripping the plant in one go.

Cause 3: Weedkiller Damage

This is where curl stops being harmless, so it is worth knowing the signs. Tomatoes are extremely sensitive to weedkiller, particularly hormone types like those used on lawns, and even a tiny amount of drift or contamination can distort them badly. The tell-tale signs are different from physiological curl: the leaves twist and curl, often downward, the new growth becomes narrow, fern-like, and distorted, stems may thicken or split, and any fruit that forms can be malformed. Crucially, weedkiller damage hits the new growth, not just the old lower leaves.

The contamination can arrive in surprising ways: spray drifting from a neighbour treating their lawn on a breezy day, or, notoriously, through manure or compost made from grass or hay treated with persistent weedkillers. If you suspect weedkiller, there is no cure, but plants with mild exposure sometimes grow out of it, so keep them watered and wait. Do not eat fruit from badly affected plants. And be careful about the manure and compost you bring in, a real risk covered in feeding the soil.

Cause 4: Virus (Uncommon in the UK)

Viruses can cause leaf curl too, but they are genuinely uncommon in UK gardens, so this should be low on your list of suspects, not high. Where they do occur, the signs go well beyond simple curling: mottled or mosaic patterning on the leaves, yellowing, purple tints in the veins, badly stunted growth, and poor or distorted fruit. Tomato yellow leaf curl virus, spread by whitefly, causes cupped, pale new leaves and stunting, but it is far more a problem of hot climates than a typical British garden.

If you genuinely suspect virus, which again is unlikely here, there is no treatment, and affected plants should be removed and destroyed to protect others, not composted. But do not jump to this conclusion, because the overwhelming majority of curl you will see in a UK garden is the harmless physiological kind, not virus. Keeping whitefly under control helps as a precaution, and good all-round plant health, as in tomato diseases, makes plants more resilient.

How to Tell Them Apart

Pulling it together, here is the quick diagnostic. If the curl is on the lower, older leaves, they stay green and leathery, and the plant is otherwise healthy and growing well, it is physiological, harmless, and needs no action beyond steadying conditions. If the new top growth is twisted, narrow, and distorted, suspect weedkiller. And if you see mottling, yellowing, purple veins, and stunting alongside the curl, only then consider virus. Nine times out of ten in a UK garden, it is the first, reassuring answer.

This is why looking closely matters so much before you act. Pulling up a perfectly healthy plant that was only reacting to cold nights would be a real shame, and it is a mistake I nearly made myself. Take a breath, check which leaves and which direction, and let the plant tell you what is going on. It is the same calm, observant approach that solves most issues in why vegetables fail.

Curling With Other Symptoms

Sometimes leaf curl comes alongside other problems, and the combination helps you diagnose. Curling with yellowing lower leaves is often just age or a feeding issue rather than anything sinister, and is covered in why tomato leaves turn yellow. Curling in a plant that is also failing to set fruit points to general stress and conditions, as in tomatoes not producing fruit. And curling with splitting fruit after erratic watering is the same watering story showing up twice, covered in why tomatoes split.

Reading the whole plant rather than one symptom in isolation is the key to getting it right. A single curled lower leaf on an otherwise thriving plant means nothing; curl plus distorted new growth plus odd fruit means something. Learning to see the pattern is what turns worried guessing into confident diagnosis, and it ties into the wider common growing problems that all reward the same close look.

Preventing Leaf Curl

Since most tomato leaves curling is a stress response, prevention is really just good tomato growing. Ventilate greenhouses well to even out the day-to-night temperature swings that cause the commonest curl. Water consistently so plants are never parched or waterlogged, support them against wind, and feed sensibly rather than forcing soft growth with too much nitrogen. Prune and remove side shoots gradually rather than all at once. Do these and the physiological curl largely disappears, or at least stops worrying you when it briefly appears.

For the serious causes, prevention means vigilance: be very careful about weedkiller near your plants and about the manure and compost you bring in, and keep whitefly down as a virus precaution. Healthy, unstressed plants in good soil, as in growing tomatoes, shrug off far more than stressed ones. Good growing is the best prevention there is, and it is all part of caring for tomato plants through the season.

When Not to Worry

I will end where I began, because it is the most important point: most tomato leaf curl is nothing to worry about. If your plant is growing well, the curl is on the lower leaves, and everything else looks healthy, you almost certainly have harmless physiological curl that will pass on its own. Resist the urge to reach for a spray or to pull the plant, because there is genuinely nothing to treat and the crop will be fine.

Save your concern for the specific warning signs, distorted new growth, twisting, strange fruit, mottling, which point to the rare serious causes. Everything else is just a tomato being a tomato in a British summer of warm days and chilly nights. Learn to tell the difference and you will save yourself a great deal of needless worry, and grow better tomatoes for the calm, as the fuller how to grow tomatoes guide sets out from the start.

Tomato Leaves Curling: Frequently Asked Questions

A Sensible Place to Start

If your tomato leaves are curling, take a close look before you do anything. If the curl is on the lower, older leaves, they are still green, and the plant is otherwise healthy and growing well, you almost certainly have the harmless physiological kind. Steady the conditions, ventilate the greenhouse, water consistently, and it will pass on its own with no effect on your crop.

Only worry if the new top growth is twisted and distorted, which points to weedkiller, or if you see mottling and stunting, which can mean virus. Both are uncommon in UK gardens. For the everyday curl that most of us see, the best thing you can do is nothing but grow the plant well. Do not let it worry you, and do not pull a perfectly good plant.

Is it too late to plant tomatoes? In the UK, the honest answer for early August is: too late to start them from seed for this year, but not necessarily too late to buy and plant an established plant if you have a greenhouse or a warm, sheltered spot. Tomatoes need a long, warm season to crop, and sowing seed now leaves nowhere near enough time for plants to grow, flower, and ripen fruit before the cold arrives. But a garden-centre plant already in flower, given warmth and shelter, can still give you a modest late crop of small or cherry tomatoes. So the real answer depends on whether you mean from seed or from a plant, and on what growing space you have. Let me walk you through exactly what is realistic now, and what to do instead if you have genuinely missed the window.

I have grown tomatoes for over twenty years on my Oxfordshire plot, and I have made this exact mistake, hopefully sowing seed far too late one hopeful July and getting nothing but leggy plants and green fruit that never ripened. So I understand the worry behind the question. Let me give you a straight, realistic answer rather than false hope, because knowing when to cut your losses and plan for next year is part of being a good gardener too.

From Seed: Yes, It Is Too Late

Let us be honest about sowing tomato seed. By August, it is too late to sow tomatoes from seed in the UK and expect a crop this year. Tomatoes need roughly five to six months from sowing to harvest, so seed sown now would not produce ripe fruit until well into the autumn or winter, long after the warmth and light have gone. You would end up nursing small, struggling plants indoors with little or nothing to show for it.

The sensible sowing window for tomatoes in the UK is late winter to early spring, typically February to April, so they are ready to plant out after the last frost. If you are reading this in August and thinking about seed, the honest advice is to wait and sow at the right time next year, which is covered fully in when to plant tomatoes. Sowing now is one of those hopeful moves that almost always disappoints.

From a Plant: Maybe, With Shelter

Buying an established plant is a different matter, and here there is a bit more hope. If you can still find a healthy tomato plant already in flower or carrying small fruit at a garden centre, and you have a greenhouse, conservatory, or a very warm, sheltered, sunny spot, it is worth a try. The plant has already done the slow early growing, so it only needs to ripen the fruit it sets, which a warm late summer can just about manage, especially with quick-ripening cherry varieties.

Be realistic about the crop, though. You are looking at a modest handful of fruit rather than a glut, and outdoors without shelter your chances drop sharply as the nights cool. Under glass, or on a warm windowsill, the odds are much better. Give the plant the same care as any tomato, steady watering and a high-potash feed, as in caring for tomato plants, and you may be pleasantly surprised by a late picking.

Why Tomatoes Need So Long

It helps to understand why the window matters so much, because it is not arbitrary. Tomatoes are warm-season plants that originated in a much hotter climate than ours, and they need a long stretch of warmth and light to grow, flower, set fruit, and then ripen it. In the UK our warm season is genuinely short, which is why timing is tighter here than in warmer countries. The RHS guide to growing tomatoes sets out the full timeline. Miss the early start and there simply are not enough warm, bright weeks left in the year to see fruit through to ripe.

This is also why so many UK tomato problems, from poor fruit set to fruit that will not ripen, come down to not enough warmth and time. Understanding your season, and your local frost dates, is the key to getting tomatoes right, and it is why the early sowing window is worth respecting rather than pushing your luck with a late one.

If You Have Green Tomatoes Now

A related worry at this time of year is not late planting but late ripening: you have plants covered in green fruit and you are wondering if they will ever turn red before the cold. The good news is that even if the season runs out, green tomatoes are not wasted. You can ripen them indoors on a windowsill or in a drawer with a banana, whose ethylene gas speeds ripening, or turn a glut of stubborn green ones into chutney.

So if your existing plants are racing the cold, do not panic. There is a full method in how to ripen green tomatoes, and it means a late or slow year still gives you a usable crop. This is a very different situation from planting late, and a much more hopeful one, since the fruit already exists and just needs coaxing to ripen.

What You Can Plant Instead

If it really is too late for tomatoes this year, the cheering news is that August is far from the end of the growing season, and plenty of other crops can still go in now for an autumn or even winter harvest. Quick salad leaves, lettuce, radishes, spring onions, and oriental greens all have time to crop before winter, and hardy crops like spinach and chard sown now will give you pickings into the colder months. It is a good moment to fill the gap the tomatoes cannot.

There is a full rundown of what still works this late in is it too late to plant vegetables and the specifics in what to sow in August. Turning your attention to these crops is far more rewarding than nursing a doomed late tomato, and keeps your garden productive right through to the end of the year. The quick, easy ones are covered in easy vegetables to grow.

Getting Ahead for Next Year

If the honest answer of too late for tomatoes has landed with a thud, the best cure is to channel that keenness into next year, when you can grow them properly from the start. Make a note now to sow your tomato seed in February or March, so your plants are strong and ready to go out after the last frost. Getting the timing right from the beginning is the single biggest factor in a good tomato year, far more than any clever trick later on, something the wider planting calendar helps you plan.

It is also worth spending the autumn and winter improving the soil where your tomatoes will go, since rich, healthy soil makes for stronger plants, as covered in improving your garden soil. Then come spring you will be ready to grow tomatoes the right way, following how to grow tomatoes from sowing to harvest. A little patience now sets up a far better crop than any rushed late planting ever could.

Growing Tomatoes in Containers Next Time

One thing worth planning for, if space or a short season is your worry, is growing tomatoes in pots next year, since containers let you start plants in a sheltered spot and move them to catch every scrap of warmth and sun. Pot-grown tomatoes can be brought under cover on cold nights and out into the sun by day, which extends their season at both ends and is a real advantage in our climate. It is one of the best ways to get a reliable crop in a tricky British summer.

There is guidance on this in growing vegetables in pots, and it applies well to tomatoes. Combined with an early start and a warm spot, container growing gives you the best possible chance of a good crop, and sidesteps the whole is it too late worry by getting you off to a strong, early, movable start. It is planning rather than panic, which is where good tomato growing always begins.

The Honest Answer

So, is it too late to plant tomatoes? From seed in August, yes, and it is kinder to tell you that plainly than to send you off on a doomed sowing. From an established plant with warmth and shelter, you have a slim but real chance of a small late crop, especially with cherry varieties under glass. And if you already have green fruit, you are not too late at all, just ripen them indoors. Match your effort to what is genuinely possible and you will not waste a season on false hope.

Above all, do not be disheartened. Every gardener has looked at the calendar in dismay at some point, and the answer is nearly always to plant something else now and get the timing right next year. Turn to the crops that still have time, plan your tomatoes properly for spring, and you will be a better and happier gardener for it. There is always something you can grow, whatever the month, as the wider tomato growing guides show.

Is It Too Late to Plant Tomatoes: Frequently Asked Questions

A Sensible Place to Start

If you are wondering whether it is too late to plant tomatoes, the honest answer is: too late from seed this year, but worth a try from an established plant if you have a greenhouse or a warm, sheltered spot and are happy with a small crop. And if you already have green fruit on the plant, you are not too late at all, simply ripen them indoors.

If it really has passed for tomatoes, do not waste the season sulking. Sow quick salad leaves and hardy greens now for an autumn crop, improve your soil over winter, and plan to sow your tomatoes in February or March next year. Get the timing right from the start and you will grow a far better crop than any rushed late planting could ever give you.

Powdery mildew is that white, dusty coating you see spreading across the leaves of courgettes, cucumbers, squash, and many other plants in late summer, and in UK gardens it is one of the most common problems going. It is a fungal disease, but not the dramatic, plant-killing kind. It looks alarming, like someone has dusted your leaves with flour, yet it rarely kills an established plant outright and is very manageable once you understand what encourages it. The single most important thing to know is that powdery mildew thrives when a plant has dry roots but humid air around its leaves, which is exactly the situation a dry spell in a crowded bed creates. Keep the roots watered and the air moving, and you prevent most of it without reaching for a single spray.

I have battled powdery mildew for over twenty years on my Oxfordshire plot, and my courgettes get it almost every August like clockwork once the nights draw in. For years I assumed it meant the end of the plant, but I learned that a mildewed courgette will often keep cropping for weeks if you manage it sensibly. Let me explain what powdery mildew actually is, why it appears when it does, and the practical, mostly non-chemical ways to deal with it.

What Powdery Mildew Looks Like

Powdery mildew is easy to recognise. It shows as a white or greyish, powdery coating on the surface of leaves, and sometimes on stems and flowers too. It usually starts as small patches, often on the upper side of older leaves, then spreads until whole leaves look dusted with white. As it worsens, affected leaves may yellow, turn brown and crisp, and die off. On a courgette or squash plant it often works its way up from the lower, older leaves first.

It is distinctive enough that you are unlikely to confuse it with much else, though it is worth knowing it sits on the leaf surface rather than within the tissue, which is why it can be rubbed off with a finger. That surface habit is also why it responds so well to good airflow and watering. If your leaves show different symptoms, spots, mould, or wilting rather than white dust, check the broader common growing problems guide instead.

Which Plants Get It

Powdery mildew affects a very wide range of plants, but some are far more prone than others. In the vegetable garden, the cucurbits are the classic victims: courgettes, cucumbers, squash, pumpkins, and marrows all get it readily, usually from midsummer onwards. Peas are another common target late in their season. Beyond vegetables, roses, apples, and many ornamentals suffer their own forms of it. Importantly, the mildew on your courgettes is a different species from the one on your roses, so it does not spread between unrelated plants.

That is a useful thing to know, because it means you do not need to panic that mildew on one crop will sweep through your whole garden. Each type is fairly specific to its host plants. The cucurbits are where most UK vegetable gardeners meet it, so if you grow courgettes, cucumbers, or pumpkins, this is a problem you will almost certainly meet at some point.

Why It Appears When It Does

Here is the part that really matters, because it holds the key to prevention. Powdery mildew is encouraged above all by dry soil at the roots combined with humid, still air around the leaves. This is why it takes hold in late summer, when plants are large and thirsty, the soil dries out between waterings, and cooler, damper nights raise the humidity around crowded foliage. Unlike most fungal diseases, powdery mildew does not need wet leaves to get going, in fact it dislikes direct water on the foliage. It is the stress of dry roots plus muggy air that lets it flourish.

That explains why the worst outbreaks come on plants that have been allowed to dry out, or that are packed too closely together with poor air movement. A well-watered plant with space around it and a breeze through its leaves is far more resistant. So the causes point straight at the cure: keep the roots consistently moist and the air moving. This is another problem that comes back to consistent watering, just as splitting and blossom end rot do on tomatoes.

How to Prevent Powdery Mildew

Prevention is far more effective than cure with powdery mildew, and it is mostly about growing conditions. Water consistently and deeply at the roots so plants never dry out and get stressed, which is the biggest single factor, and mulch around the base to hold that moisture in. Give plants plenty of space when you plant them so air can move freely through the foliage, because crowded, still air is what mildew loves. And water the soil rather than the leaves, keeping the foliage dry while the roots stay moist.

Good soil that holds moisture steadily makes a real difference too, since it stops the roots drying out in the first place, which is one more reason to keep improving your garden soil and building good soil health. Feeding sensibly rather than forcing lush, soft growth helps as well, as covered in feeding the soil not the plant. Get these conditions right and mildew becomes an occasional nuisance rather than an annual certainty.

How to Deal With It Once It Appears

If mildew has already taken hold, do not despair, because you can slow it right down and often keep the plant cropping. Start by removing the worst-affected leaves, cutting off any that are heavily coated in white and disposing of them, not on the compost heap, to reduce the spores in the area. This also opens the plant up and improves airflow, which helps in itself. Then get on top of the watering, giving the roots a consistent deep drink, since a well-watered plant copes far better.

Improving air movement around the plant by thinning congested growth, and by not crowding neighbouring plants, slows the spread noticeably. On a plant like a courgette that is already well established, this management alone will often see it through to the end of the season still producing. The mildew may not vanish, but the plant keeps going, which is usually all you need in late summer, as I explain in caring for stressed plants and why plants struggle under stress.

Should You Use a Fungicide?

My honest view, which matches the RHS position, is that for edible crops in the home garden you are usually better off without fungicides. The RHS advice on powdery mildew actively recommends against using them, partly because they can harm the wider biodiversity and soil life of your garden, and partly because good cultural care, watering, spacing, and removing affected leaves, manages mildew perfectly well in most cases. By the time mildew appears on a late-summer courgette, the plant is often near the end of its productive life anyway, so spraying rarely earns its keep.

You may have heard of homemade milk or bicarbonate sprays. The evidence for these is mixed and the RHS does not recommend homemade preparations, since they are unregulated and untested, so I would not rely on them. Far better to put your energy into the watering, spacing, and airflow that genuinely work. Managing the conditions is the real answer, not a bottle, which fits the whole approach in why vegetables fail.

Can You Eat Affected Crops?

Yes, and this reassures a lot of worried gardeners. Powdery mildew grows on the surface of the plant, so courgettes, cucumbers, and squash from a mildewed plant are perfectly safe to eat. The fruit itself is rarely affected, and even where a little mildew is on the skin it can be washed or wiped off. There is no need to throw away your crop just because the leaves have gone white.

So keep picking and eating as normal. What mildew does over time is weaken the plant and reduce how much it produces, rather than making the existing crop inedible. Harvest what is there, manage the plant to keep it going as long as you can, and enjoy the produce. A mildewed courgette plant in September is still a courgette plant worth having.

Choosing Resistant Varieties

If powdery mildew is a yearly frustration on a particular crop, it is well worth seeking out varieties bred to resist it. Many modern courgette, cucumber, and squash varieties are described as mildew-resistant or mildew-tolerant, and while no plant is completely immune, these hold out noticeably longer and crop later into the season. It is one of the easiest wins available, since you simply choose a better variety at seed-buying time.

Combine a resistant variety with good watering and spacing and you may barely see mildew at all, or at least not until the very end of the season when it hardly matters. Choosing the right variety from the start saves a great deal of bother, a theme that runs through growing vegetables generally. It is prevention built in before you even sow.

Living With Late-Summer Mildew

The honest truth is that a bit of powdery mildew on your courgettes come late August is almost a rite of passage in a UK garden, and not something to lose sleep over. By that point in the season the plants have usually given you a generous crop already, and a little white on the leaves is the plant winding down rather than a disaster. Manage it, keep picking, and accept that some mildew at the tail end of summer is normal even in a well-run garden.

What matters is not letting it take hold early through dry, stressed, crowded growing, because that is when it genuinely costs you crop. Water well, space generously, choose resistant varieties, and you push mildew back to the very end of the season where it belongs. Do that and you will grow strong, productive courgettes and cucumbers year after year, mildew or no mildew, alongside everything else in your problem-solving toolkit.

Powdery Mildew: Frequently Asked Questions

A Sensible Place to Start

If powdery mildew has appeared, do not panic and do not reach for a spray. Remove the worst white-coated leaves, get on top of the watering so the roots stay consistently moist, and open the plant up to improve airflow. That management alone will usually keep a courgette or cucumber cropping to the end of the season.

To prevent it next year, the answer is watering, spacing, and a mildew-resistant variety. Keep the roots moist, give plants room to breathe, and choose varieties bred to resist it. Do that and mildew becomes a minor late-season nuisance rather than an annual problem. And remember, the crop is perfectly good to eat throughout, so keep picking and enjoy it.

Why are my tomatoes splitting? Tomatoes split when they take up water faster than their skins can stretch, and in UK gardens the usual trigger is a spell of dry weather followed by heavy rain or a big watering. The fruit swells suddenly on the inside, the skin cannot keep up, and it cracks. It looks alarming, but split tomatoes are not diseased, not dangerous, and almost always caused by inconsistent watering rather than anything wrong with the plant. You can still eat them, and once you understand what causes the splitting you can largely prevent it. The fix, as with so many tomato problems, comes down to steady, even watering rather than the feast-and-famine that our weather so often delivers.

I have grown tomatoes for over twenty years on my Oxfordshire clay, in the greenhouse and outdoors, and splitting used to frustrate me every summer, especially after a dry fortnight broke into a downpour and half my ripening fruit cracked overnight. Once I understood it was a watering and weather problem rather than a disease, I stopped worrying and started managing it, and it became far less of an issue. Let me explain exactly why tomatoes split, the two different kinds of splitting you will see, and how to stop it happening.

Why Tomatoes Split

The cause is beautifully simple once you picture it. A tomato has a skin that can only stretch so fast. When the plant suddenly takes up a lot of water, after rain or a heavy watering following a dry spell, the flesh inside swells quickly, the skin cannot expand to match, and it splits. It is purely a matter of the inside growing faster than the outside can accommodate. That is why splitting so often appears the morning after rain breaks a dry period, and why it clusters on the fruit closest to ripening, whose skins are least elastic.

So splitting is not an infection, a pest, or a nutrient problem. It is a physical response to a sudden change in water uptake, which means the answer lies entirely in how evenly the plant is watered and how sheltered it is from sudden downpours. This puts it in the same family as blossom end rot, another watering-related disorder, and it is worth reading the two together since the prevention overlaps so much.

The Two Types of Splitting

There are two patterns of splitting, and it helps to know which you are seeing, though the cause and cure are much the same. The first is radial splitting, where the cracks run down the sides of the fruit from the stalk towards the base, like the segments of an orange. This is the more common type and usually follows a sharp change in watering. The second is concentric splitting, where the cracks form rings around the shoulders of the tomato near the stalk, often finer and more circular.

Radial cracks tend to result from a sudden big drink after drought, while concentric ring-cracks are more often linked to fluctuating conditions over a longer period, and some varieties are simply more prone to them. Either way, both come back to uneven water and, sometimes, big temperature swings. Knowing the type is mostly reassurance that you are looking at splitting and not a disease, which is covered in tomato diseases and the wider common tomato problems guide.

It Is Not a Disease

This is worth stating plainly, because a cracked tomato can look unpleasant and set off worries about blight or rot. Splitting itself is not a disease. It is a physical crack caused by water, and the fruit underneath is perfectly sound at the moment it splits. There is no fungus or bacteria involved in the splitting, and it does not spread from fruit to fruit or plant to plant the way an actual disease would. The RHS advice on tomato splitting confirms it is a physiological disorder, so sprays are no help.

The one caveat is what happens next. An open split is a wound, and if you leave a cracked tomato on the plant in damp weather, that broken skin can let in moulds and rots or attract fruit flies. So the split is not the disease, but it can become a doorway for one if ignored. That is why the practical advice is to pick split fruit promptly, which I come to below. For genuine disease worries, tomato blight is the one to rule out.

How to Stop Tomatoes Splitting

Prevention is almost entirely about consistent watering, so this is where to focus. Water regularly and evenly so the plant never dries out and then gets flooded, which for containers in warm weather usually means a good drink every day, sometimes twice in a heatwave. The aim is to keep the soil steadily moist rather than letting it swing between bone dry and soaking, because it is the swing, not the amount, that splits the fruit. Getting into a daily rhythm rather than watering only when you remember makes the single biggest difference.

Mulching around the base of your plants helps enormously, because it holds moisture in the soil and evens out the ups and downs. Improving the soil so it retains water more steadily helps too, which is another reason to keep improving your garden soil and to think about how often to water. For outdoor tomatoes, a bit of shelter from heavy rain, growing against a wall or under a lean-to, reduces the sudden soakings that cause the worst splitting.

Why Greenhouse Tomatoes Split Too

You might expect a greenhouse to prevent splitting, since it keeps the rain off, and it does help with the downpour problem. But greenhouse tomatoes split for a different reason: heat. On a hot day a greenhouse can soar, the plants transpire hard and dry out fast, and then when you water in the evening they take up a big drink all at once, which splits the fruit just as rain would outdoors. The enclosed heat actually makes consistent watering more important, not less.

So under glass the answers are good ventilation to stop the extreme heat, shading in the hottest spells, and steady watering rather than one big evening soak after a dry, baking day. Damping down the greenhouse floor helps keep the air and roots more even too. It is all part of the same care routine covered in caring for tomato plants and growing tomatoes generally.

Can You Eat Split Tomatoes?

Yes, and this is the reassuring part. A tomato that has just split is perfectly good to eat, since the crack is only skin-deep and the flesh is sound. The sensible approach is to pick split fruit as soon as you spot it, before the open wound has a chance to attract mould or fruit flies, and use it promptly. A freshly split tomato is exactly as good in the kitchen as a whole one, so there is no waste involved in catching them early.

The only ones to discard are those you missed, where the split has been sitting open in damp weather and has started to rot or grow mould. Those go on the compost heap. But caught promptly, split tomatoes are a minor cosmetic problem rather than a loss, and if a glut of them splits after rain, they are ideal for cooking down into sauces and soups. If some are still green when they split, you can also ripen them indoors.

Some Varieties Split More Than Others

It is worth knowing that variety plays a real part. Thin-skinned varieties and many cherry tomatoes are more prone to splitting than thicker-skinned types, simply because their skins are less able to stretch. Some heritage and beefsteak varieties also crack readily. If you grow a variety that splits badly every year despite your best watering, the variety itself may be part of the problem, and it is not necessarily anything you are doing wrong.

If splitting is a perennial frustration, it is worth trying a variety described as crack-resistant next season, alongside your usual steady watering. Many modern varieties are bred to resist splitting well. Choosing the right variety from the start, as touched on in how to grow tomatoes, saves a lot of bother, though good watering still matters whatever you grow.

Splitting, Blossom End Rot, and Watering

If you take a step back, you will notice that the big three tomato fruit problems all trace to the same root. Splitting, blossom end rot, and poor fruit set are all, at heart, watering and consistency problems. Get the watering steady and even, and you prevent all three at once, which is why consistent watering is the most valuable single habit you can build as a tomato grower. It is genuinely the master key to healthy fruit.

That is oddly encouraging, because it means you are not fighting three separate battles but one. Steady watering, good soil that holds moisture, mulch, and shelter from extremes solve the lot. It ties into the broader picture of common growing problems and why vegetables fail, nearly all of which come back to conditions rather than bad luck.

Why Tomatoes Are Worth the Trouble

Splitting, like most tomato troubles, is really the plant asking for more consistent care, and once you provide it the problem fades. Tomatoes are more demanding than the easy beginner crops, but they teach you to water well and read your plants, and those skills pay off across everything else you grow. A split tomato is simply feedback: the watering has been uneven, steady it up, and the next flush comes through clean.

So do not be disheartened if a batch cracks after summer rain, because it happens to every tomato grower, myself included, most years. Pick them, use them, adjust the watering, and carry on. If you want the fuller picture of growing strong, healthy plants from the start, when to plant tomatoes and feeding them properly both help you get ahead of problems like this before they begin.

Why Are My Tomatoes Splitting: Frequently Asked Questions

A Sensible Place to Start

If your tomatoes are splitting, the fix is almost always the same: steady the watering. Water regularly and evenly so the soil stays consistently moist rather than swinging between bone dry and soaked, which for pots and grow bags usually means watering daily, or twice a day in hot weather. Mulch around the base to hold moisture, and shelter outdoor plants from sudden heavy rain where you can.

Meanwhile, pick any split fruit promptly and use it, since it is perfectly good caught early. Get the watering steady and most of the splitting stops, and you will have solved blossom end rot and poor fruit set into the bargain, since all three come back to the same thing. Consistent watering really is the master key to healthy tomatoes.

Blossom end rot on tomatoes shows up as a sunken, dark, leathery patch on the bottom of the fruit, and in UK gardens it is almost always caused by uneven watering rather than by any disease or pest. Despite the alarming name, it is not a rot you catch and it is not something spreading through your plants. It is the fruit’s way of telling you that the plant could not move enough calcium to the developing tomato at a critical moment, and the usual reason for that is the soil drying out and then getting soaked, over and over. The reassuring part is that it is very fixable, and often preventable, once you understand what is really going on. Steady the watering and most plants stop producing affected fruit within a couple of weeks.

I have grown tomatoes for over twenty years, in the greenhouse and outdoors on heavy Oxfordshire clay, and blossom end rot used to catch me out every summer, especially with plants in pots and grow bags. Once I understood it was a watering problem and not a disease, I stopped reaching for sprays and started fixing the actual cause, and it largely disappeared. Let me explain exactly what it is, how to be sure that is what you are looking at, and how to put it right.

What Blossom End Rot Looks Like

Blossom end rot is unmistakable once you have seen it. It starts as a small, water-soaked or pale patch at the blossom end of the fruit, which is the bottom, opposite the stalk. That patch then darkens, sinks inwards, and turns brown or black and leathery, sometimes covering a third or more of the tomato. It affects the fruit only, not the leaves or stems, and it appears on green, developing fruit rather than ripe ones. The affected area feels flat and dry rather than soft and mushy.

This is the key thing that tells it apart from an actual disease: it always appears on the bottom of the fruit, it is dry and leathery rather than fuzzy or oozing, and it does not spread from plant to plant. If you are seeing dark patches elsewhere, or mould, or affected leaves, you are likely looking at something else, which I cover in tomato diseases and the broader common tomato problems guide.

It Is Not a Disease

This is the single most important thing to understand, because it changes everything about how you deal with it. Blossom end rot is not caused by a fungus, bacteria, or pest. You cannot catch it, spray it away, or pass it between plants. It is what is called a physiological disorder, which is a fancy way of saying the plant’s growing conditions went wrong rather than something attacked it. So no fungicide will help, and reaching for one is wasted effort and money. The RHS advice on blossom end rot confirms it is a physiological disorder rather than a disease.

Because it is a conditions problem, the fix is always about how you are growing and watering the plant, never about treating a disease. That is genuinely good news, because it means the cause is within your control. Get the conditions right and the problem stops. This is a recurring theme with tomatoes, where most troubles trace back to growing conditions rather than infection, as I explain in why vegetables fail.

The Real Cause: Calcium and Water

Blossom end rot happens when the developing fruit cannot get enough calcium at the right moment. Calcium builds the cell walls in the growing tomato, and when there is a shortfall as the fruit swells, the tissue at the far end breaks down and you get that dark, sunken patch. So far so simple. But here is the part people miss: the problem is almost never a lack of calcium in your soil. UK garden soils, and shop-bought composts, nearly always contain plenty.

The real issue is that the plant cannot move the calcium it has to where it is needed, and the thing that carries calcium around a plant is water. When watering is erratic, the soil drying out and then being flooded, the plant’s uptake is disrupted and calcium delivery to the fruit stutters at exactly the wrong time. So blossom end rot is really a watering problem wearing a calcium costume. Fix the water and you fix the calcium delivery, which is why steady moisture matters so much, as covered in how often to water plants.

Why It Hits Pots and Grow Bags Most

If your affected plants are in containers, grow bags, or pots, that is no coincidence. Container-grown tomatoes are far more prone to blossom end rot than those in the ground, and the reason is simple: pots and grow bags dry out fast, then get watered heavily, then dry out again, which is exactly the erratic moisture that triggers the problem. The limited compost cannot buffer the swings the way open ground can. Grow bags are the worst offenders because they hold so little compost.

This is why the same variety can be perfect in a border and plagued in a grow bag a few feet away. It is not the plant, it is the growing conditions. If you grow tomatoes in pots, you simply have to be more disciplined about consistent watering, and it helps to choose the largest containers you reasonably can. There is more on getting containers right in growing vegetables in pots.

How to Fix It

The fix is almost entirely about watering, so this is where to put your effort. Water regularly and consistently so the compost or soil never swings between bone dry and soaking, which for containers in warm weather usually means watering daily, sometimes twice a day in a hot spell. Aim to keep the soil evenly moist, like a wrung-out sponge, rather than alternating between drought and flood. This one change solves the majority of cases on its own.

Alongside steady watering, mulch the surface of beds and large pots to hold moisture and even out the swings, and avoid over-feeding with high-nitrogen fertiliser, which pushes fast growth that outpaces calcium delivery and makes things worse. Do not bother with calcium sprays or adding lime unless a soil test actually shows a deficiency, because the calcium is almost always already there. The affected fruit will not recover, so pick them off, but the plant’s future fruit should be fine once watering is steady.

How to Prevent It Next Time

Prevention is the same medicine as the cure, applied from the start. Set up for consistent watering before problems appear: choose large containers that dry out more slowly, or grow in the ground where you can, mulch to stabilise moisture, and get into a steady watering routine rather than watering only when you remember. A self-watering setup or even a simple timer can help enormously with container tomatoes, because consistency is everything.

Building good soil that holds moisture evenly also makes a real difference over time, because a soil rich in organic matter buffers the swings that cause the problem. That is another reason to keep improving your soil and to think in terms of feeding the soil rather than the plant. Strong, healthy plants in good soil rarely suffer badly, which ties into overall soil health.

Can You Still Eat Affected Tomatoes?

A common worry, and the answer is reassuring: yes, you can eat the unaffected part. Blossom end rot is not a disease or a toxin, so if you simply cut away the dark, leathery patch at the bottom, the rest of the tomato is perfectly good to eat. It will not taste any different. Many gardeners do exactly this with early affected fruit rather than waste it, though badly affected tomatoes with a large rotten area are usually best composted.

So there is no need to bin a whole crop over a few marked fruit. Cut, use what is good, and focus your attention on steadying the watering so the next flush comes through clean. Once you have the watering sorted, the later fruit almost always forms perfectly.

It Affects More Than Tomatoes

Although tomatoes are where most people meet it, blossom end rot shows up on other fruiting crops too, for exactly the same reason. Peppers, chillies, courgettes, and aubergines can all develop the same dark, sunken patch at the blossom end when watering is erratic, particularly in pots. So if you see it on your peppers as well as your tomatoes, it is the same problem and the same fix: steady the water.

Recognising it across different crops saves a lot of worry, because once you know the cause you treat them all the same way. It is one of those disorders that looks like several different problems but is really just one, showing up wherever fruit swells fastest and water is least consistent. This sits within the wider set of common growing problems that trace back to watering and soil.

When It Keeps Coming Back

If blossom end rot returns year after year despite your best efforts, the culprit is nearly always a growing setup that makes consistent watering hard, usually grow bags or small pots that dry out too fast to keep up with. The answer is to change the setup rather than fight it: move to larger containers or open ground, improve the soil so it holds moisture, and mulch well. Do not keep blaming the plant or the variety, because it is the conditions that need changing.

It is also worth remembering that a bad heatwave can trigger a flush of blossom end rot even in a well-run garden, simply because the plants cannot drink fast enough to keep up. That kind of weather-driven bout usually passes once conditions ease, so do not despair over it. For the rest, steady watering and good soil are the long-term answer, part of the same care routine as the rest of caring for tomato plants through the season.

Why Tomatoes Teach You to Water Well

Blossom end rot is annoying, but it is also a useful teacher, because it makes visible something that is true of all your growing: consistent watering matters more than almost anything else. A tomato showing blossom end rot is really just telling you, in dramatic fashion, that its watering has been up and down. Learn to keep it steady for your tomatoes and you will grow everything better, because the same principle applies right across the plot.

So do not be disheartened if it appears. Read it as feedback, steady the water, and move on. Every tomato grower has met it, and fixing it is one of those small skills that quietly makes you a better gardener. If you want the fuller picture of growing healthy plants from the start, my guide to growing tomatoes pulls it all together, and tomatoes not producing fruit covers the other big watering-related worry.

Blossom End Rot on Tomatoes: Frequently Asked Questions

A Sensible Place to Start

If you spot blossom end rot on your tomatoes, do not panic and do not reach for a spray. Remember it is a watering problem, not a disease. Start by steadying your watering so the soil stays evenly moist rather than swinging between dry and soaked, which for pots and grow bags usually means watering daily, or twice a day in hot weather. Mulch the surface to help, and ease off any high-nitrogen feed.

Pick off the affected fruit, since it will not recover, and keep the watering consistent. Within a couple of weeks the new fruit should come through clean. Get into a steady watering routine and good soil, and blossom end rot usually stops being a problem at all. It is one of those garden worries that looks serious but turns out to be simple once you know what it is really telling you.

Is it too late to plant peas? In the UK it depends on where you are and which month you have reached, but the short answer for late summer is: it is borderline, and often worth a gamble. A quick early variety sown in early August can still crop in October in the milder south, though you are racing the autumn. Sow in July and you have a comfortable chance of a late crop; sow much past mid August and only the mildest gardens will ripen pods before the cold shuts things down. So if you have a spare row and a packet of a fast early pea, it is well worth a punt, as long as you go in with your eyes open about the odds.

Peas are one of those crops people assume have a narrow spring-only window, and every year I have gardeners on my heavy Oxfordshire clay ask me in July whether they have missed the boat entirely. The honest answer is more encouraging than they expect. Peas are hardy, they germinate happily in warm soil, and a late sowing has one real advantage over a spring one that almost nobody mentions. Let me talk you through when a late pea sowing works, when it genuinely is too late, and how to give a gamble sowing the best possible chance.

The Honest Answer, Month by Month

July

Not too late at all. A sowing in July, particularly early July, is a genuinely good late sowing that will crop from September into October across most of the country. This is the sweet spot for a second flush of peas, and if you sowed in spring, a July sowing keeps the harvest going once the first lot is over. Choose a quick early variety rather than a maincrop, and you are on solid ground.

Early August

Borderline, and this is where the gamble lives. In the milder south and west, a fast early pea sown in the first week or two of August can just about crop in October before the weather turns. In the North and Scotland the odds are longer, because your first frosts arrive weeks earlier. It is worth trying if you have the space, but treat anything you harvest as a bonus rather than a certainty.

Late August and Beyond

For a crop of pods this year, yes, this is realistically too late almost everywhere. There simply are not enough warm growing days left for the plants to flower and fill pods before the cold stops them. But there is one clever exception worth knowing about, covered below: a late sowing of a hardy round-seeded variety made now can overwinter and give you the earliest crop of all next spring.

Why Late Peas Can Actually Do Better

Here is the part that surprises people. Peas are a cool-season crop. They dislike heat, and in a hot summer a spring-sown crop often struggles the moment the temperature climbs, growing poorly, suffering mildew, and giving tough, starchy pods. A late crop that does its main growing as the weather cools into September dodges all of that. The plants romp away in the mild, damp conditions they actually prefer, and the pods that form are sweet and tender rather than mealy.

So a late sowing is not just a desperate gamble on beating the frost, it is genuinely playing to the pea’s strengths. The one thing you are trading is time: you need the crop to mature before the cold, whereas in spring you have the whole summer ahead. Get a fast variety in early enough and you get the best of both, cool growing conditions and enough season to finish.

Choose a Fast Early Variety

For any late sowing, variety choice is what makes or breaks it. You want a first early, round-seeded pea, the quickest type there is, maturing in around eleven to twelve weeks rather than the fourteen-plus of a maincrop. Old reliable names like Feltham First, Meteor and Kelvedon Wonder are exactly the sort to reach for, bred to be fast and hardy. Avoid the tall maincrop and marrowfat types now, as they simply take too long. A packet of quick early pea seed costs very little, which is part of why a late gamble is so worth taking: the downside is a couple of pounds and a bit of space, the upside is fresh October peas.

Those same hardy round-seeded earlies are the ones to use for the overwintering trick. Sown in late October or November in a sheltered, well-drained spot, they sit through winter as small sturdy plants and race away in early spring to give you peas weeks before anything spring-sown. It is the one late sowing that is not a gamble at all, just a different plan.

Giving a Late Sowing Its Best Chance

A few things tilt the odds in your favour when you are sowing late. Sow into moist soil and keep it watered, because late summer ground can be dry and peas need consistent moisture to germinate and swell their pods. Get supports in early, as even dwarf peas crop better with a few twiggy sticks or netting to climb. And protect the young shoots from birds and mice, which are the two great enemies of pea seedlings, with a bit of netting or some twiggy cover.

Most usefully of all, have some horticultural fleece to hand for the autumn. Thrown over the row on the first cold nights, it buys you a week or two of extra growing time and can be the difference between filled pods and a near miss. In a cold-frame or against a warm south-facing wall, a late crop does even better. Every little bit of warmth you can steal at the back end of the season counts when you are racing the frost.

If It Really Is Too Late, Sow This Instead

If you have reached late August in a colder part of the country and a pea crop this year looks unlikely, do not leave the ground bare. Late summer is prime time for fast salads and hardy leaves that will crop through autumn, so a row of the things that genuinely thrive now is a better use of the space. There is a full rundown in what to sow in August and what to sow in September.

And peas are far from the only crop people ask about at this time of year. The full picture of what can and cannot still go in is set out in the main guide to whether it is too late to plant vegetables, which covers every common crop at a glance. Beans are the closest relative worth checking, since runner beans and french beans follow slightly different late-season rules.

The Full Picture on Growing Peas

Whether you are gambling on a late crop or planning properly for next year, the wider detail on getting peas right is worth having. The best sowing windows through the whole year are laid out in when to plant peas, and peas sit alongside everything else in the vegetable planting calendar. If you are just getting started, the beginner’s guide and the general how to grow vegetables pages will set you up.

Peas are a forgiving, cheerful crop, and their willingness to grow well in the cool shoulders of the year is exactly what makes a late sowing worth trying. Whatever the calendar says, a spare row and a packet of fast earlies is rarely a wasted effort, and there are few nicer things in October than a handful of sweet peas you were told you had left too late to grow.

Is It Too Late to Plant Peas? Frequently Asked Questions

A Sensible Place to Start

If you are reading this in July or early August wondering whether to bother, my advice is simple: bother. Get hold of a packet of a fast first early pea, sow a short row into moist soil this week, and give it a fair go. The cost is trivial and the cool autumn conditions are on your side more than you would think.

If the calendar has slipped past mid August, switch tack. Either sow fast salads and hardy leaves now for an autumn harvest, or note down the overwintering pea trick for late autumn, which gives you the earliest peas of all next year. Whichever you choose, the ground need never sit empty, and peas will be back in the plan before you know it.

Is it too late to plant vegetables? In the UK, the honest answer for early August is: for some crops yes, but for plenty of others there is still time, and a surprising amount can go in now for an autumn or even winter harvest. The crops whose window has closed are the long-season, heat-loving ones like tomatoes, pumpkins and runner beans from seed. But fast crops like salad leaves, radishes, spring onions and turnips can still be sown, and hardy vegetables for autumn and winter are exactly right for now. The table below gives you a straight yes or no for the vegetables people most often ask about, so scroll down, find your crop, and you will know where you stand.

I have lost count of the number of times, over twenty-odd years growing on heavy Oxfordshire clay, that I have stood over a bare patch of ground in July or August wondering if there was any point sowing anything. The instinct is to think the growing year is over by midsummer. It is not. The sowing year has two halves, and the second one, the autumn and winter crops, is one that beginners almost always miss. So before you write the season off, let me talk you through what is genuinely too late, what is still worth a go, and what you should actually be sowing right now instead.

Is It Too Late to Plant Vegetables? The Quick Answer Table

This table is for early to mid August, the point in the season when most people start asking the question. Dates shift a little with your region and the weather, and everything is a week or two more generous in the mild South West and tighter in the North and Scotland. Where a crop is borderline, I have said so honestly rather than pretending.

The Crops That Really Have Missed the Boat

Let me be straight, because there is no kindness in pretending. If you are reading this in August, the heat-loving, long-season crops are done for the year from seed, and no amount of optimism will change it. Tomatoes, pumpkins, squash, sweetcorn, cucumbers and courgettes all need the entire summer to grow, flower, and ripen fruit, and there simply are not enough warm weeks left. A tomato seed sown now would still be a small green plant when the first frosts kill it.

The same goes for runner beans from seed and maincrop onions. If you already have established plants of any of these, that is completely different, keep looking after them and they will crop into autumn until the frost stops them. But starting them from scratch now is throwing seed away. The honest move is to note the right time in the vegetable planting calendar for next year, and turn your attention to what actually will grow.

What You Should Be Sowing Right Now Instead

Here is the part beginners miss, and it is genuinely cheering. Late summer is not the end of sowing, it is the start of the autumn and winter growing season, and there is a whole set of crops that positively prefer to go in now. Fast salad crops are the obvious win: lettuce, rocket, radishes, spring onions and turnips are all ready in a matter of weeks, and many of them grow better now than in the heat of high summer, when lettuce bolts and rocket runs to seed.

Then there are the hardy autumn and winter vegetables that are exactly on time: spinach, chard, oriental leaves like pak choi and mizuna, spring cabbage, and overwintering varieties that sit through the cold and crop early next year. This is also the moment for autumn-planting onion sets and garlic as September approaches. There is a full rundown in what to sow in August and what to sow in September, which are the two pages to bookmark right now.

The Borderline Crops Worth a Gamble

Some crops sit right on the edge in August, and whether they work depends on your region, the variety, and a bit of luck with the autumn. I am a great believer in the cheap gamble here: a packet of seed costs little, an empty bed earns nothing, so if you have the space it is worth a punt on the borderline crops even knowing they might not fully mature.

A quick early pea variety sown in early August can crop in October in the milder half of the country, though it is too late to plant tomatoes from seed by now, and there is a full guide to whether it is too late to plant peas where you are. Dwarf French beans, being faster than runners, are just about worth trying very early in the month down south. And second-cropping seed potatoes, a special late-planting type, go in now to give you fresh new potatoes at Christmas, which is one of the nicest tricks in the whole gardening year. In the North and Scotland these gambles are longer odds, so lean instead on the reliable fast salads and hardy leaves. A bit of horticultural fleece to hand extends every one of these windows by warming the soil and buying you a couple of extra weeks in autumn.

Where You Garden Changes the Answer

Every date on this page shifts with your location, and it matters more in late summer than at any other time, because you are racing the first frost. In the South West and the milder south, autumn arrives late and you have the most generous windows, so the borderline crops are genuinely worth trying. Across the Midlands, treat the dates here as written. In northern England and Scotland the first frost comes weeks earlier, so be stricter: stick to the fast, reliable crops and the hardy overwintering leaves, and do not gamble on anything that needs to mature before the cold.

The single most useful thing you can know here is your own average first frost date, because that is the finish line everything is running towards. It is worth checking against the UK frost dates by postcode, and remember a greenhouse, cold frame or even a cloche effectively moves you a zone south by keeping the frost off. Growing in pots and containers helps too, since you can move them somewhere sheltered as the nights draw in.

Why Late Sowing Is a Habit Worth Keeping

Once you get into the rhythm of it, you stop seeing August as the end of anything. The gardeners who harvest something in every month of the year are not doing anything clever, they are simply sowing hardy crops in late summer while everyone else assumes the season is over. A row of spinach, some winter salad leaves, spring cabbage and a few autumn-planted onions will give you fresh food right through the lean months when the shops are at their most expensive.

So the answer to “is it too late” is almost never a flat yes. It is too late for that particular crop, perhaps, but there is nearly always something you can sow instead. If you are just getting going, the beginner’s guide and the general how to grow vegetables pages will set you up, and the August gardening jobs list keeps you right on everything else that needs doing this month.

Is It Too Late to Plant Vegetables? Frequently Asked Questions

A Sensible Place to Start

If you have found this page in a bit of a panic that you have left it too late, take a breath, because you almost certainly have not. Pick two or three of the crops marked “No” in the table, a fast salad and a hardy leaf, and get them sown this week into warm, moist soil. They will be up within days and cropping within weeks, and you will have proved to yourself that the season is far from over.

Then get into the habit, every year, of treating late summer as a second sowing season rather than the end of the first. Bookmark the August and September sowing guides, keep a packet of fast salad seed and some fleece to hand, and you will find you are harvesting something fresh in months when most gardens are bare. That, more than any single crop, is the trick worth learning.

How to ripen green tomatoes, the quickest method is to pick them and put them in a bowl or paper bag with a ripe banana, somewhere warm and dark, and they will turn red in a week or two. On the plant, you speed things up by removing the lower leaves, pinching out the growing tip in late summer, and easing off the watering so the plant stops making new growth and puts its energy into the fruit it already has. Warmth is what actually does the work, not sunlight, which is the bit most people get wrong.

Every August I have the same conversation with someone over a fence: plants loaded with tomatoes, not one of them turning red, and a growing worry that the whole lot is going to waste. If your plants are only just going in, though, it may be too late to plant tomatoes at all this year. It is one of the most common questions I get, and the good news is that ripening is easy to nudge along once you understand what the plant is actually waiting for. After twenty years of growing them on heavy Oxfordshire clay, I have tried most of the tricks, and a few of them genuinely work while the rest are folklore.

Why Tomatoes Go Red: It Is Warmth, Not Sun

Here is the thing almost everyone gets wrong, myself included for years. Tomatoes do not need direct sunlight to ripen. They need warmth, and they need a gas called ethylene, which the fruit produces itself. Sunlight helps the plant grow and it warms the fruit, but a green tomato will ripen perfectly well in a dark drawer as long as it is warm enough.

The sweet spot is roughly 20 to 24C. Below about 10C ripening more or less stops, which is why the crop stalls as autumn cools. And here is the counter-intuitive part that catches people out in a hot summer: above about 30C the plant stops making lycopene, the pigment that turns tomatoes red, so in a heatwave your fruit can sit stubbornly green or turn a patchy yellowish orange. If that is happening to you, the plant is not sick, it is too hot, and there is nothing to do but wait for the weather to settle. The RHS covers the growing side in detail if you want the background.

Once you understand it is about warmth rather than light, every method below makes sense, because they are all just ways of keeping the fruit warm and surrounded by ethylene.

How to Ripen Green Tomatoes on the Vine

If the plant is healthy and there is still warmth left in the season, the best tomatoes are the ones you ripen on the plant. You just help it along. The single most effective thing is to stop the plant growing, because as long as it is putting out new leaves and flowers it is spending energy on growth rather than ripening. From early to mid August, pinch out the very top of each cordon plant two leaves above the highest truss you want to keep. This is called stopping, and it tells the plant the season is ending.

At the same time, strip off the lower leaves up to the first truss of fruit. This lets light and warm air get at the trusses and improves airflow, which also cuts the risk of disease. Keep removing any new side shoots too, the same way you would earlier in the season, which I cover in removing side shoots on tomatoes. Finally, ease back on watering. A plant that thinks a drought is coming panics slightly and throws its energy into ripening the fruit it has, so slightly drier is better than lush at this stage. Just do not let it wilt hard. There is more on getting that balance right in how often to water, and the wider late-summer care sits in how to care for tomato plants.

How to Ripen Tomatoes Indoors, Off the Vine

Sometimes waiting on the vine is not an option. The nights have turned, blight is threatening, or the season is simply over. When that happens, pick the green tomatoes and ripen them indoors, which works far better than most people expect once you know it is ethylene doing the job.

The classic method is a paper bag or a bowl with a ripe banana or apple, which pump out ethylene and set the tomatoes off. Keep them somewhere warm, around 18 to 21C, and out of direct sun, which can scald them. Check every couple of days and remove any that are ripening or, worse, going soft, because one rotting fruit will take the rest with it. A single layer in a cardboard box lined with newspaper works just as well as anything fancy. Wrapping individual fruits in newspaper slows them down if you want to spread the harvest out over weeks rather than have them all at once.

One tip worth knowing: only fruit that has reached full size and started to lighten from dark to pale green, or shown the first blush of colour, will ripen well indoors. A tiny hard dark-green tomato picked in September has not developed enough and will more likely shrivel than redden, so those are the ones for chutney.

Ripening a Whole Plant at the End of the Season

When frost is forecast and a plant is still covered in green fruit, do not pick them one by one. Lift the whole plant, roots and all, and hang it upside down somewhere warm and dry like a shed, a garage or a spare room. The fruit keeps drawing on the plant and ripens gradually over the following weeks, and you get a much better result than picking everything green in a panic.

If frost has not quite arrived but is close, you can also buy a week or two outdoors by covering the plants at night. A layer of garden fleece thrown over the row on cold nights holds enough warmth to keep ripening ticking along and protects the fruit from a light frost. Knowing when your first frost is likely helps you plan all of this, and the frost date checker gives a date for your postcode. Clearing the last of the tomatoes is one of the jobs I list in August gardening jobs, and it dovetails with what to sow in September as the beds start to clear.

How to Ripen Tomatoes Quickly

If you want the fastest result, the banana-in-a-paper-bag method is hard to beat. The confined space concentrates the ethylene from the banana around the tomatoes, and in real warmth they will often colour up in three to five days rather than the week to two weeks a bowl on the side takes. An apple does the same job if you have no banana.

What does not work is the internet advice you will see about ripening them on a sunny windowsill. It is the most common suggestion and one of the worst, because a windowsill cooks one side in direct sun while the fruit stays cool, and you end up with soft, unevenly coloured tomatoes with tough patches. Warm and shaded beats bright and hot every time. There is no genuine way to ripen a tomato overnight, whatever you read, but the paper bag is as close as it gets.

Why Your Tomatoes Might Not Be Ripening

If the fruit is simply refusing to turn red on the plant, it is usually one of a handful of causes, and none of them means the plant is beyond help. Cool weather is the most common in a British summer, since ripening slows below 10C and the plant is just waiting for warmth. A heatwave is the opposite problem, stalling the colour above 30C. Too much leafy growth is another, where the plant is busy growing rather than ripening, which is exactly what the stopping and leaf-stripping above fixes.

Overfeeding, especially with a high-nitrogen feed, pushes the same leafy growth at the expense of fruit, so switch to a high-potash tomato feed once fruit has set. And sometimes it is simply too late a crop, where plants that went in late are only fruiting as the light fades. If your plants are struggling in other ways as well, it is worth working through common tomato problems, and if they are flowering but not even setting fruit, that is a different issue covered in tomato plants not producing fruit. Yellowing leaves alongside slow ripening point to why tomato leaves turn yellow.

What to Do With the Green Ones That Never Turn

Every year there are stragglers, the small hard green tomatoes that were never going to ripen. Do not bin them. Green tomato chutney is one of the genuine pleasures of the end of the tomato season, and it turns a glut of unripe fruit into jars of something you will still be enjoying at Christmas. Fried green tomatoes are worth a go too if you have never tried them.

I have come to see the green ones not as a failure but as a second harvest, and it takes the anxiety out of that first frost warning. Whatever has not ripened becomes chutney, and nothing is wasted. The BBC Gardeners’ World tomato guide has more on end-of-season care if you want another view.

Getting Ahead of It Next Year

Half the ripening battle is won long before August, at planting time. The single biggest cause of a late, green-heavy crop is starting too late, so plants that go in on time have the whole warm season to fruit and ripen. My guide to when to plant tomatoes covers the timing, and growing tomatoes in the UK pulls the whole thing together.

Variety matters too. Cherry types like Sungold ripen far earlier and more reliably in our climate than big beefsteaks, which often run out of summer before they colour up. And a greenhouse changes everything, holding the warmth that ripens fruit and extending the season at both ends. If you are still getting seedlings established each spring, how to grow tomatoes and why tomato seedlings go leggy will help you raise stronger plants that fruit earlier. Outdoors, growing a blight-resistant variety also means you are less likely to be forced into picking everything green because blight has struck, which is a common reason people end up ripening indoors in the first place.

How to Ripen Green Tomatoes: Frequently Asked Questions

A Sensible Place to Start

If your tomatoes are green and you are not sure what to do, start with the simplest thing. Pick a few of the biggest, put them in a bowl with a ripe banana somewhere warm, and watch them turn over the next week. That one small experiment shows you it is warmth and ethylene doing the work, not sunshine, and once you trust that, the rest falls into place.

For the fruit still on the plant, stop it growing in August, strip the lower leaves, and let the season do its job. And when the first frost warning comes, do not panic-pick everything green. Ripen what you can indoors and turn the rest into chutney. Handled that way, the end of the tomato season stops being a race against the weather and becomes just another part of the harvest.

I spent my first few years at war with greenfly and my last fifteen more or less ignoring them, and the plants have never been better. What changed was noticing what happened when I did nothing. One June I gave up on a badly infested row of broad beans, too busy to deal with them, and came back ten days later to find the colonies crawling with ladybird larvae and the plants cropping perfectly well. That was the year I stopped spraying anything, and the greenfly have been someone else’s problem ever since.

Greenfly, Blackfly and What They Actually Are

Greenfly and blackfly are not different pests, they are different aphids, and there are hundreds of species in the UK. What they share is a way of life: they pierce soft plant tissue and drink the sap, breeding at a speed that is genuinely hard to believe. In warm weather females give birth to live young without needing to mate, and those young are themselves pregnant when born, which is how a handful of aphids becomes a solid colony in a week. Greenfly are the pale green ones you find on rose buds and shoot tips. Blackfly, properly the black bean aphid, are the sooty black clusters that smother the growing tips of broad beans in early summer, and they also hit runner beans, dahlias and nasturtiums. Woolly aphids are a different creature again, appearing as white fluffy patches on apple branches and woody stems.

How to Spot the Damage

Look at the softest, newest growth first, because that is where they always start: the tips of shoots, the undersides of young leaves, and flower buds just before they open. You will see dense clusters of small soft-bodied insects, often with winged individuals among them once the colony gets crowded. The signs that go with them are as telling as the aphids themselves. Leaves become sticky with honeydew, the sugary waste they excrete, which then grows a black film of sooty mould. New shoots curl, pucker and distort, and buds may fail to open properly. And you will often notice ants running up and down the stems, because ants farm aphids for that honeydew and will actively protect them from predators, so a stream of ants on a rose is a reliable sign of greenfly above.

What to Do About Them, Honestly

Start with your fingers. Running a colony between finger and thumb takes seconds and kills hundreds, and on roses and beans that is usually the whole job. A sharp jet of water from a hose knocks off most of what remains, and aphids that fall off rarely find their way back up. For a heavy infestation on a tough plant, a very weak solution of plain soap in water sprayed onto the colonies works by breaking down their outer coating, though use it sparingly and never in strong sun, because it can scorch soft leaves and it kills beneficial insects it lands on just as readily. Pinching out the top few inches of broad beans once the lower pods have set removes the blackfly and the tender growth they want in one go, and it is standard practice on any allotment worth the name. What I would not do is reach for a spray as a first resort. Most of what is sold to home gardeners is either ineffective, short-lived, or kills the ladybirds, hoverfly larvae and parasitic wasps that are your actual solution, which is how people end up with a worse infestation a fortnight later than the one they sprayed.

Let the Ladybirds Do It

The single most useful thing to understand about greenfly is the timing. Aphids wake up and breed earlier in the year than the things that eat them, which is why late May and June feel like an invasion. Give it two or three weeks and the predators catch up, at which point the colonies collapse fast. A single ladybird can eat fifty aphids a day, and its larvae, those odd little blue-grey alligator things with orange spots that people often mistake for pests and squash, eat far more. Hoverfly larvae are even better, and lacewings, earwigs, tiny parasitic wasps and blue tits all pile in too. Learn to recognise ladybird larvae and leave them alone, because killing them is the most common own goal in the garden. Planting flowers among the vegetables brings the predators in earlier and keeps them there, which is one of the practical arguments in bee friendly plants. Hoverflies in particular want open, simple flowers such as calendula, poached egg plant and single marigolds.

Greenfly on Roses

Roses get greenfly every single year and it is worth saying plainly that a rose covered in greenfly in June is not in danger. The damage is cosmetic on an established plant, some distorted buds and sticky leaves, and by July it is generally over. Squash what you can reach, hose the rest, and resist spraying, because roses are magnets for ladybirds precisely because they carry aphids, and a sprayed rose loses that population for the season. If the same rose is badly infested year after year, look at how soft the growth is, since heavy nitrogen feeding produces exactly the lush sappy shoots aphids prefer. Ease off the feed and you get fewer greenfly, the same principle that applies to soft growth on vegetables.

Blackfly on Broad Beans

This is the one aphid problem that genuinely needs action, because a heavy blackfly infestation on broad beans really does reduce the crop. The colonies target the soft growing tip, so the fix is to remove it. Once the plants have set four or five trusses of pods at the bottom, pinch out the top four inches or so, which takes away both the blackfly and the growth they are heading for, and pushes the plant into filling the pods it already has. Do it as a matter of routine in early summer rather than waiting for the blackfly to arrive. Autumn-sown beans usually escape the worst of it altogether because they are further ahead by the time the aphids appear, which is one of the quieter arguments for autumn sowing covered in how to grow broad beans. If a few colonies remain lower down the plant after pinching, squash them and leave the rest to the ladybirds.

Keeping Numbers Down Next Year

Prevention here is mostly about not creating the conditions aphids love. Go easy on high-nitrogen feeds, because soft sappy growth is what draws them in, and a plant fed steadily rather than pushed hard is noticeably less troubled. Water consistently, since stressed plants attract more pests, and inconsistent watering causes plenty of other problems besides, as covered in how often to water. Grow flowers among the vegetables to keep predators resident rather than visiting. Check plants weekly in May and June and squash the first small colonies before they become large ones, which is five minutes that saves an hour. And accept a background level of aphids as normal and even useful, because a garden with no aphids at all is a garden with no ladybirds either, and that is a worse position to be in when the next wave arrives.

Frequently Asked Questions

A Sensible Place to Start

Do the cheap things and wait. Squash the colonies you can see, hose down the rest, pinch the tops out of your broad beans once the bottom pods have set, and then leave it alone for a fortnight. Learn what a ladybird larva looks like so you stop killing your own allies. Ease off the nitrogen feed on anything that gets hit year after year, and put a few open flowers in among the vegetables so the predators are already living there when the aphids arrive. That is the entire strategy, it costs nothing, and it works better than anything in a bottle. The year I stopped fighting greenfly was the year I stopped having a greenfly problem.

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The first year I grew brassicas properly I did everything right except the one thing that mattered. Beautiful cabbages, well fed, well watered, and I stood back rather proud of them in late July. Ten days later I lifted a leaf and the underside was crawling. Not a few caterpillars, hundreds, and the plants were more hole than leaf. I had watched the pretty white butterflies flitting about the plot all month and thought nothing of it. That is the whole lesson of this article in one story: the butterfly you ignore in June is the ruined crop you find in August.

Which Butterfly, Which Caterpillar

Two species do nearly all the damage, and it helps to know them apart because they behave differently. The large white is the bigger butterfly, with bold black wing tips, and it lays clusters of yellow, skittle-shaped eggs on the undersides of leaves. Its caterpillars are yellow and grey-green with black blotches, hairy, and they feed in gangs out in the open, often stripping the outer leaves first. The small white is slightly smaller with less black on the wings, and it lays single eggs rather than clusters. Its caterpillars are velvety green, well camouflaged against the leaf, and they burrow into the heart of a cabbage where you cannot see them, which makes them the sneakier of the two. There is also the cabbage moth, whose brown caterpillars do the same job at night. In practice you treat all of them the same way, but the large white is the one you usually spot first because it is so much more obvious.

How to Tell Caterpillars Are the Problem

The damage is distinctive once you know it. You will see ragged holes eaten through the leaves, often starting at the edges and working in, and on a bad infestation only the tough leaf veins left behind, giving that skeletal look. Look for the caterpillars themselves on the undersides of leaves and tucked into the growing heart, and for scatterings of dark green or brown frass, which is a polite word for caterpillar droppings, on the lower leaves and around the plant. Above all, check the leaf undersides for the eggs before they even hatch: the large white lays neat clusters of upright yellow eggs, and finding and rubbing those off is ten seconds of work that saves you a hundred caterpillars later. If the holes are accompanied by silvery slime trails instead of frass, you are dealing with slugs and snails rather than caterpillars, which is a different problem with a different answer.

The Only Thing That Really Works: Netting Them Out

Prevention beats cure so completely with this pest that it is worth saying plainly: the single most effective thing you can do is stop the butterflies ever reaching the plants. A physical barrier of fine insect mesh, put over the brassicas from May and kept on through summer, means no eggs, no caterpillars, and no work beyond checking it now and then. Ordinary butterfly netting with a mesh around 7mm is enough to keep both cabbage whites out, and it is the one piece of kit I would not grow brassicas without after that first disastrous year. The two things that matter in using it: hold it clear of the foliage on hoops or canes, because a butterfly will happily lay through mesh that is resting on a leaf, and tuck the edges right down to the soil or weigh them with stones, because they will find any gap. A tunnel of netting over a bed of cabbages is not the prettiest thing on the plot, but it is the difference between whole leaves and lace.

What to Do If They Are Already Here

If the caterpillars have already arrived, and in a British summer they will find unprotected plants within weeks, the honest answer is hands and vigilance rather than a magic bottle. Go over the plants at least twice a week, more in warm weather, and check the undersides of leaves and deep into the hearts. Rub off any egg clusters, and pick off and squash or drop into soapy water every caterpillar you find. It is not glamorous but it genuinely works if you are consistent, because you are breaking the cycle before the next generation lays. On a heavy infestation, a strong jet of water knocks many off, and standing the outer leaves back to expose the caterpillars to birds helps too. The biological control Bacillus thuringiensis, a naturally occurring bacterium sold for caterpillar control, is the one genuinely effective treatment beyond hand-picking, though availability to UK amateurs varies, so check what is currently sold before relying on it. What does not work well is most general bug sprays, which struggle to reach caterpillars tucked into a cabbage heart and which also kill the ladybirds and hoverflies you want to keep.

Working With Nature Instead of Against It

You do not have to wage total war. Cabbage white caterpillars have plenty of natural enemies, and a garden that encourages them suffers less. Birds, especially in spring, eat huge numbers, so leaving some access rather than netting absolutely everything has a place. A tiny parasitic wasp, Cotesia glomerata, lays its eggs inside large white caterpillars, and those sickly caterpillars surrounded by little yellow cocoons are the wasp doing your job for you, so leave them be. Growing some flowers among the veg to bring in hoverflies and other predators helps the whole plot, which is one of the arguments in my piece on plants for pollinators. Some gardeners plant nasturtiums as a sacrificial crop that the whites lay on in preference, though in my experience that just breeds more butterflies unless you then remove the caterpillars, so treat it as a decoy you still have to police, not a fix.

Keeping Brassicas Healthy Enough to Cope

A strong plant shrugs off light damage that would set back a weak one, so good growing is part of pest control. Firm planting, steady moisture and sensible feeding all help, and the brassica cluster on this site covers each in turn: growing brassicas for the overview, feeding without soft growth, since soft sappy growth from too much nitrogen is exactly what pests love, and watering brassicas properly. Net the plants, keep them growing steadily, check them twice a week through summer, and you will eat the cabbages instead of watching the caterpillars eat them. It really does come down to those few habits, and the netting is the one that does most of the work.

Frequently Asked Questions

A Sensible Place to Start

If you grow brassicas, buy the netting before you need it, not after. Put it over the plants in May on hoops that hold it clear of the leaves, tuck the edges down to the soil, and you have solved the problem before it starts. If the caterpillars are already among your cabbages this summer, do not despair and do not bother with sprays: get into a rhythm of checking the leaf undersides twice a week, rubbing off the yellow eggs and picking off the caterpillars, and you will save the crop. It is ten minutes that feels like a chore and pays you back in whole, unlaced cabbages. I learned that the hard way, standing over a bed of skeletons one August, and I have never grown a brassica uncovered since. Getting the netting on early, right from when you plant your brassicas out, is what keeps them clean.