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
Is it too late to plant tomatoes in August in the UK?
From seed, yes. Tomatoes need five to six months to crop, so August-sown seed will not ripen before winter. From an established plant with a greenhouse or warm sheltered spot, you may still get a small late crop, especially with cherry varieties.
Can I still grow tomatoes from seed in August?
Not for a crop this year. Seed sown in August leaves nowhere near enough warm, bright weeks for plants to grow, flower and ripen fruit. The right sowing window is February to April. Wait and sow at the proper time next year for a real crop.
Will a shop-bought tomato plant fruit if I plant it now?
Possibly, if it is already in flower or carrying small fruit and you have a greenhouse, conservatory or very warm sheltered spot. It has done the slow early growing, so it just needs to ripen fruit. Expect a modest crop rather than a glut.
What can I plant instead of tomatoes in August?
Plenty. Quick salad leaves, lettuce, radishes, spring onions and oriental greens all still have time to crop, and hardy spinach and chard sown now will give pickings into winter. August is far from the end of the growing season.
My tomatoes are still green in late summer, what do I do?
You are not too late at all, the fruit just needs ripening. Ripen green tomatoes indoors on a windowsill or in a drawer with a banana, whose ethylene speeds things up, or turn a glut into green tomato chutney. Nothing is wasted.
When should I plant tomatoes in the UK?
Sow seed indoors from late winter to early spring, typically February to April, then plant out after the last frost once nights are reliably warm. This early start gives the long warm season tomatoes need to crop well.
Can I grow tomatoes indoors over winter in the UK?
It is very difficult without heated, well-lit growing space, as our winter light and warmth are too low for good fruiting. A sunny heated conservatory might manage a little, but for most gardeners it is better to wait and sow at the right time in spring.
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.