Overview
What tomatoes need, when they crop, and whether they suit your space.
A tomato picked ripe and still warm from the sun tastes better than anything in the shops, and that is the whole case for growing your own. Tomatoes began as desert plants, domesticated in Mexico and the Andes, so they love heat and have little natural defence against the diseases of damp summers. Choose well and one plant can give you 2.75 to 5 kg (6 to 11 lb) of fruit.
Quick facts
- Botanical name
- Solanum lycopersicum
- Soil pH
- 6.0 – 6.8
- Feeding
- Heavy feeder
- Temperature
- 16 – 32 °C
- Hardiness
- Any zone, as an annual
- Time to harvest
- 60 – 100 days
- Height
- Up to 200 cm (79 in)
- Propagation
- Seed, Cutting
Optimal growth
Keep above 10 °C
Growing details
- Germination
- 6 – 12 days
- Spacing
- 45 cm (18 in)
- Sowing depth
- 3 mm (⅛ in)
- Frost sensitivity
- Frost tender
Growing calendar
- Start indoors: 4 to 7 weeks before your last frost
- Transplant: 1 to 2 weeks after your last frost
- Flowering: June, July, August
- Harvest: July, August, September, October
In a cool temperate climate; earlier under cover. From midsummer in a cool temperate climate; under cover it starts earlier and runs into autumn.
Is this plant right for you?
- Container friendly
- Raised-bed friendly
- Grow bags
- Greenhouse friendly
- Self-pollinating
- Needs support
- Frost tender
Toxic to pets
The plant contains solanine and is toxic to dogs, cats and horses. The ripe fruit is non-toxic.
Before You Grow
Pick a type that fits your season and space, then give it the warmest, sunniest spot you have.
Check the seed packet for the habit, the days to harvest and any disease resistance.
What you need
Seed, or young plants
Weigh the two up in the comparison alongside. If you buy, choose short, sturdy, dark green plants with no flowers or fruit yet.
The warmest, sunniest spot you have
Full sun, sheltered from wind. See where tomatoes grow best.
A bed, a large pot or a growing bag
All three work. See containers for pot sizes.
A stake, cage or string
It goes in at planting time, so have it ready before you start.
Compost, mulch and a tomato feed
Garden compost for the ground, straw or compost to mulch it, and a high-potassium liquid feed. See feeding.
Choose your tomato type
Two decisions change how you grow the plant: its growth habit and its fruit type. Settle the habit first, because it decides the spacing, the support and whether you prune at all.
Cordon (indeterminate) varieties keep growing and flowering until frost or until you stop them. They grow 1.5 to 2 m (5 to 6½ ft) tall and take little ground space, but need a support and attention every week. In return you get a long, staggered harvest.
Bush (determinate) varieties grow to a set size and ripen most of their crop at once, usually early. They need little maintenance, which makes them the best start for a beginner. They suit containers, short seasons and anyone who wants a batch for sauce.
Semi-determinate varieties sit between the two: more compact than a cordon, but they keep cropping until frost.
Trailing varieties are compact bush types whose stems cascade over the side of a window box or hanging basket.
Grafted plants cost more and come in fewer varieties, but they are more vigorous, crop earlier and heavier, and resist more diseases.
Then choose the fruit. The table below compares the types.
- Cordon: a long harvest from a small footprint, with support and pruning.
- Bush: one early crop and little maintenance, good in pots.
- Trailing: bush types for window boxes and hanging baskets.
- Had wilt or blight before? Look for disease resistance on the packet.
Fruit types compared
-
Cherry
- Fruit
- Small, bite-sized
- Ripens
- Soonest
- Best for
- Eating raw, snacking
-
Salad
- Fruit
- Medium, round and even
- Ripens
- In between
- Best for
- Salads and sandwiches
-
Plum or paste
- Fruit
- Elongated and firm
- Ripens
- In between
- Best for
- Sauce, cooking, preserving
-
Beefsteak
- Fruit
- Large, often ribbed
- Ripens
- Last
- Best for
- Slicing and cooking
Match the type to your kitchen: cherry and salad types to eat raw, plum and beefsteak to cook. Smaller fruit ripens sooner, so in a short summer lean towards cherries.
Where tomatoes grow best
Tomatoes want the warmest, sunniest, most sheltered spot you have, in soil that drains well but holds moisture.
Light. At least six hours of direct sun a day for a good crop, and eight or more is better. Shade costs you fruit.
Temperature. Tomatoes need days reliably above about 16 °C (60 °F), and fruit sets poorly above about 32 °C (90 °F). They are tender: frost damages or kills them, and cold soil and air stress them.
Soil. Deep, fertile and well drained, with plenty of organic matter. Clay and loam give the biggest crops; light soils warm up sooner and give an earlier one. They do best at pH 6.0 to 6.8 and tolerate down to about 5.5.
Rotation. Don’t plant where tomatoes, potatoes, peppers or aubergines grew in the last two years. Root diseases build up in the soil.
Outdoors or under cover. Outdoors, choose a warm, sheltered spot. A greenhouse or polytunnel gives a longer season and usually more fruit, but it gets hot. Ventilate whenever the weather allows, and shade the glass in hot spells, a little at a time.
Planting
Sow indoors, harden off gently, and plant out deep once the frosts are over.
Have stakes, mulch and fleece ready before planting day.
When to plant tomatoes
Work backwards from the day you plan to plant out, and set that by your last frost, not by the calendar.
Sow indoors five to eight weeks before you plan to plant out. Don’t start too early: a plant that is too big when it goes out often stalls, and younger plants overtake it.
Plant out a week or two after your last frost. Wait until nights stay above 7 °C (45 °F) and days are reliably above 16 °C (60 °F).
Under cover, in a greenhouse or polytunnel, sow about a month earlier than for plants going outdoors.
- Sow indoors 5 to 8 weeks before planting out.
- Plant out 1 to 2 weeks after your last frost.
- Wait for nights above 7 °C (45 °F) and days reliably above 16 °C (60 °F).
How to grow tomatoes from seed
Tomato seed needs warmth, not light, to germinate. Light matters from the moment the seedlings appear.
-
Fill trays or cells with seed compost
Use a peat-free seed compost. Water it and let it drain before you sow.
-
Sow 3 mm (⅛ in) deep
Sow into cells, or space the seeds well apart in a tray. Cover them with a thin layer of compost or vermiculite. Label them: tomato seedlings all look alike.
-
Keep them warm
Seed germinates slowly from about 16 °C (60 °F) and fastest at 24 to 32 °C (75 to 90 °F), so aim for 18 °C (64 °F) or more. Use a heated propagator, or a warm windowsill with a clear bag over the pot. Expect seedlings in 6 to 12 days, about a week at 24 °C (75 °F).
-
Give them strong light the day they emerge
Take the cover off and give them all the light you can. Even a sunny south-facing window is barely enough, so a grow light helps. Low light makes seedlings thin and leggy.
-
Water from below
When the compost needs water, stand the pot in shallow water for up to an hour. Compost kept too wet invites damping off, a fungal disease that kills seedlings.
-
Pot on when the first true leaves appear
Move each seedling to its own 8 cm (3 in) pot of multi-purpose compost. Hold it by a leaf, not the stem, and set it deep, with the seed leaves just above the surface.
-
Grow on at about 21 °C (70 °F)
Keep them bright and never below 16 °C (60 °F). If the roots fill the pot before it is time to plant out, move them to a slightly bigger one.
How to plant out
Plant into warm soil, and put the support in at the same time.
-
Harden off over one to two weeks
Start with a few hours in shade, out of the wind, and give the plants a little longer in the sun each day. Cut back water and feed a little at the same time. Don’t harden plants off by exposing them to cold: chilling stunts them.
-
Deal with peat or coir pots
Tear off the rim, or bury it completely. An exposed rim wicks water away from the roots.
-
Plant deeper than it grew in the pot
Set the plant so its lowest leaves sit just above the soil, stripping any leaves that would be buried. Roots form all along the buried stem and give a stronger root system.
-
Space 45 to 60 cm (18 to 24 in) apart
That suits staked plants and bush types. Give plants in cages 60 to 90 cm (2 to 3 ft), and plants left to sprawl 90 to 120 cm (3 to 4 ft). Leave 1.2 to 1.5 m (4 to 5 ft) between rows. Crowding invites leaf disease.
-
Put the support in now
Drive a stake at least 20 to 25 cm (8 to 10 in) into the ground beside the plant, or set a cage over it. Doing it now means you won’t spear the roots later.
-
Water in well
Soak the soil around the base to settle it against the roots.
-
Mulch once the soil is warm
Spread 5 to 8 cm (2 to 3 in) of straw, compost or shredded leaves around the plant, keeping it clear of the stem. Mulch holds moisture, keeps soil off the leaves and fruit, and cuts disease. Don’t use clippings from a lawn treated with weedkiller until it has been mown two or three times.
-
Protect it early in the season
Fleece or a cloche on cold nights helps the plant settle. Take covers off whenever the day goes above about 29 °C (85 °F).
Care
Even watering, the right feed at the right time, and a support that keeps pace with the plant.
Check plants every week: tie in, take out side shoots, and look under the leaves for pests.
Care by growth stage
Seedling
Light: as much as possible · Water: from below, never soggy · Feed: none yet
Warmth to germinate, then all the light you can give. See growing from seed.
Establishment
Water: deeply, to settle the roots · Feed: not yet · Mulch: once the soil is warm · Protect: on cold nights
The first weeks after planting out. Water it in and hold off feeding. See how to plant out.
Vegetative growth
Water: evenly · Support: tie in every week or so · Prune: side shoots on cordons only
Fast growth of leaves and stems. See support, pruning and training.
Flowering
Water: evenly · Feed: starts about now · Under cover: ventilate
Fruit set depends on temperature and, under cover, on moving air. See flowers and fruit set.
Fruiting
Water: never let it dry out · Feed: high potassium · Stop: cordons at the top of the support
End of season
Clear: dispose of diseased leaves and stems · Rotate: a new bed next year
Help the last fruit ripen, then pick everything before the frost. See harvesting.
Watering tomatoes
Aim for about 25 mm (1 in) of water a week, rain included, so the soil stays evenly moist. Uneven watering, dry and then soaked, causes split fruit and blossom-end rot (see common problems).
How to water. In the morning, at the base of the plant, straight onto the soil. Keep water off the leaves: splashing spreads leaf diseases such as Septoria.
How often. Check the soil rather than keeping to a schedule, and water when the top few centimetres feel dry. Sandy soil needs water more often, in smaller amounts; the weekly total stays the same. Even moisture matters most once the fruit is forming.
Plants in pots dry out much faster. See containers.
- About 25 mm (1 in) a week, rain included.
- Check the soil, not the calendar.
- At the base, in the morning, not over the leaves.
- Mulch to keep the moisture even.
Feeding tomatoes
Feed lightly until the first fruits start to swell, then switch to a high-potassium feed.
Before planting, dig well-rotted compost or manure into the bed, never fresh manure. Without a soil test, a general-purpose fertiliser worked in before planting is enough.
After planting out, wait three to four weeks before feeding plants in the ground.
Once the fruit starts to swell, feed every 10 to 14 days with a high-potassium liquid feed such as a tomato feed. That is the RHS advice; Gardeners’ World starts sooner, feeding weekly from the first flowers. Plants in rich ground may not strictly need it, but regular feeding raises the yield. Plants in pots and growing bags do need it.
Signs it needs more. Pale leaves, slow growth and few fruit, most often in pots, where the compost runs out first.
Support, pruning and training
Whether you prune depends on the variety’s habit, so check the label first.
Cordon (indeterminate) plants are trained up a single stem. At least once a week, snap out the side shoots that grow in the joint between the main stem and a leaf, while they are 5 to 10 cm (2 to 4 in) long. Tie the stem loosely to its stake as it grows, or wind it round its string.
Stop cordons by pinching out the growing tip two leaves above the top truss. Do it when the plant reaches the top of its support, or once it has four or five trusses outdoors, six or seven under cover.
Bush (determinate) plants need no side-shooting and no stopping. Prop up heavy trusses on an upturned flowerpot or a short cane so the stems don’t snap.
What pruning trades. Staking and pruning bring the first harvest a week or more earlier and give larger, cleaner fruit with less leaf disease. The sources split on the total crop: Cornell finds it usually smaller, Iowa State says pruning raises it. Pruned plants are more prone to blossom-end rot and sunscald.
Lower leaves. Take them off later in the season, as they yellow or die. That lets light reach the ripening fruit and helps keep grey mould away.
Support choices. A stake about 1.8 m (6 ft) long suits a cordon; tie it in with soft string in a figure of eight. A wire cage about 55 cm (22 in) across suits bush and sprawling types. Under cover, string from an overhead wire, anchored under the rootball at planting, is the standard.
Flowers and fruit set
Tomato flowers pollinate themselves: each carries both parts and only needs shaking to shed pollen. Outdoors, wind and insects do that for you.
Under cover, open the vents often so insects can reach the flowers. Tap or gently shake the open flowers to move the pollen; misting them with water can help too.
Temperature decides fruit set. Flowers drop without setting fruit when days go above about 32 °C (90 °F) or nights fall below about 13 °C (55 °F). Heavy rain can have the same effect.
Too much nitrogen also cuts fruit set. See feeding.
Growing tomatoes in containers
Tomatoes crop well in pots and growing bags, as long as you accept that you are now their entire water supply.
Pot size. One plant per pot at least 30 cm (12 in) wide and deep, up to 45 cm (18 in) for a big cordon. Bush and dwarf types suit large patio pots and troughs, and trailing types window boxes and hanging baskets.
Growing bags. Two plants in a standard bag, or up to three in a deep one.
Compost. Peat-free loam-based or multi-purpose potting compost.
Water. Check every day: pots may need watering daily in hot weather.
Feed. In a pot, regular feeding is essential. See feeding.
Growing tomatoes indoors
Indoors, light is the limit. Even a sunny south-facing window is barely enough for seedlings, so plan on a grow light.
Choose a small variety. Dwarf, miniature and trailing bush types fit a pot on a sill.
Pollinate by hand. There is no wind or insect to do it indoors. See flowers and fruit set.
Water and feed as for any container. See containers.
What to plant with tomatoes
Companion planting claims range from well evidenced to folklore. Each one here is labelled with the evidence behind it.
Basil and other herbs
Grow together · Wants the same conditions
They share the tomato’s need for sun and warmth and fit at its feet. Their strong scent may confuse pests.
French marigolds
Grow together · Traditional practice
Their strong smell is thought to deter whitefly, a common pest under cover.
Potatoes
Keep apart · Agronomic reason
Both get late blight, and one can pass it to the other. Keep them apart, and rotate both.
Tall or vigorous plants
Keep apart · Agronomic reason
Anything that shades tomatoes or competes for food costs you fruit, and crowding cuts the airflow that keeps disease down.
Problems
What goes wrong with the fruit, flowers and leaves, the pests and diseases behind it, and what to do about each.
Common tomato problems
These are growing problems, not pests or diseases.
Sunken dark patch on the base of the fruit
- Uneven watering
- Calcium
Blossom-end rot. The fruit is short of calcium, more often because the plant can’t take it up than because the soil lacks it. Uneven watering, damaged roots and too much nitrogen all make it worse. Keep watering even, mulch, and don’t dig close to the plants. It often shows on the first fruits formed.
Split or cracked fruit
- Water swing
- Heavy rain after drought
After a dry spell, heavy rain or a big watering makes the fruit take up water too fast and the skin cracks. Keep the soil evenly moist and mulch.
Misshapen, scarred fruit
- Cold at flowering
Catfacing: incomplete pollination, usually in cold weather. Young plants chilled before or after planting out are more prone to it, so don’t rush planting out (see when to plant).
Pale, papery patch on the sunny side of the fruit
- Sunscald
- Too few leaves
Sunscald: fruit exposed to strong sun with no leaf cover. Don’t strip the leaves that shade the fruit.
Flowers fall without setting fruit
- Heat
- Cold nights
- Still air
Usually temperature. Heavy rain, too much nitrogen and, under cover, still air play a part too. See flowers and fruit set.
Fruit slow to ripen, or ripening orange and blotchy
- Cool weather
- Heat above 32 °C
Cool, cloudy weather slows ripening. Above 32 °C (90 °F) the red colour doesn’t form, so red varieties ripen yellow-orange. Under glass, heat also brings tough skins and blotchy ripening (see where tomatoes grow best for shading).
Yellow leaves
- Age
- Watering
- Disease
Lower leaves yellowing late in the season is the plant ageing; take them off then. Yellowing elsewhere has many causes, from watering to disease. See why tomato leaves turn yellow.
More problems with tomatoes
Common pests
Tomato hornworm
A large green caterpillar that strips leaves fast. Pick it off by hand. Natural enemies often keep it in check.
Aphids
Small sap-suckers clustered on new growth. Knock them off with a hard jet of water, early in the day. Look for natural enemies, such as ladybird and lacewing larvae, before you do anything else.
Whitefly
Tiny white sap-suckers that weaken plants and can spread disease, mostly under cover. Check bought plants and don’t bring infested ones home. Control an outbreak with Encarsia, a biological control. French marigolds may help deter them (see companions).
Flea beetles
They chew young leaves early in the season. Cover plants with fleece at planting and take it off before the weather gets hot. Keep the bed weeded.
Cutworms
Young plants cut off at soil level overnight. A cardboard collar round each stem at planting protects them; keeping the bed weeded helps too.
Green shield bugs
Often found on tomatoes and harmless. They won’t damage the crop, so leave them be.
More problems with tomatoes
Common diseases
Very few diseases can be diagnosed accurately by eye. If you’re unsure, send a sample or photos to your local extension service or plant clinic before you act.
Late blight
Leaves, stems and fruit rot fast in warm, wet weather. It is the same disease as potato blight. It mostly hits outdoor plants, though greenhouse plants can catch it in a bad year. Remove affected plants promptly and grow resistant varieties, such as ‘Crimson Crush’, where summers are damp.
Early blight and Septoria leaf spot
Leaf-spot diseases. Septoria starts on the lower leaves, early in the season, in cool, wet weather. Keep water off the leaves, space plants for airflow, and remove affected leaves when they are dry. In autumn, clear away all diseased leaves and stems.
Grey mould
Fuzzy grey mould on fruit and stems in cool, damp weather, mostly under cover. Check plants often, remove and bin affected fruit, ventilate, and thin out dense foliage.
Fusarium and verticillium wilt
Soil-borne diseases that make plants wilt. Prevention is the only defence: rotate beds (see where tomatoes grow best) and choose varieties bred to resist them.
More problems with tomatoes
Harvest & Use
Pick by colour, not by the calendar, and ripen the last green fruit indoors.
Harvesting tomatoes
Pick when the fruit is fully and evenly coloured and gives slightly under gentle pressure. Colour is the reliable sign. The days to harvest on the packet are an estimate, counted from planting out, not sowing.
How to pick. Pick each fruit with its stalk attached. Check plants every few days and pick often: overripe fruit splits, spoils and attracts disease.
End of season. To hurry the last fruit, remove any new flowers and stop cordons if you haven’t. Before the first frost, pick every full-sized fruit, green ones included. Or lift whole plants and hang them upside down somewhere cool and dark, picking the fruit as it ripens. See storing and ripening.
- Full, even colour plus a slight give means ripe.
- Pick with the stalk attached.
- Pick every few days while the plants are cropping.
- Clear the plants before the first frost.
Storing and ripening
Ripe tomatoes keep for about a week at room temperature, out of direct sun. Avoid the fridge where you can: cold makes them mushy. If you must, refrigerate only fully ripe fruit, for a few days at most.
Green tomatoes ripen indoors if they are mature: full size and turning pale greenish-white. Wrap each one in newspaper and store them in a single layer somewhere cool and dark, at 16 to 18 °C (60 to 65 °F). Check them often and remove any that soften or rot. Once they start to colour, unwrap them and finish them at room temperature. A banana beside them speeds things up.
Gluts. Whole tomatoes freeze poorly, so cook them into sauce and freeze that. They also dry, juice and make good chutney. If you bottle them, follow a tested preserving recipe.
Propagation
Save seed from open-pollinated varieties, or root a side shoot to keep a favourite going.
Saving seed and next season
Save seed only from open-pollinated or heirloom varieties. Hybrid (F1) plants don’t come true from seed and often give poorer fruit, so buy fresh seed to grow them again. Open-pollinated seed comes true as long as the plant hasn’t crossed with another variety.
To save seed, pick a fully ripe fruit from your healthiest plant. Scoop the seeds and their gel into a jar with a little water and leave it for a few days. Rinse the seeds clean and dry them on a plate. Store them in a labelled envelope somewhere cool, dry and dark.
To root a cutting, take a strong side shoot and strip its lower leaves. Stand it in water or moist potting compost, and pot it up once it has roots.
More to Explore
Quick answers, guides that pair well with tomatoes, and the sources behind this one.
Frequently asked questions
How long do tomatoes take to grow?
About 60 to 100 days from planting out to the first ripe fruit. Early varieties take 65 days or less, late ones 80 or more. Add five to eight weeks if you start from seed.
How much sun do tomatoes need?
At least six hours of direct sun a day, and eight or more is better. With less, expect a smaller crop.
How often should I water tomatoes?
There’s no fixed schedule. Aim for about 25 mm (1 in) a week, rain included, and keep the soil evenly moist. Pots may need watering every day in hot weather.
Can I grow tomatoes in a pot?
Yes. Use one plant per pot at least 30 cm (12 in) wide and deep, or two per growing bag, and feed regularly once the fruit starts to swell.
Do tomatoes need a greenhouse?
No. They grow outdoors in a warm, sunny, sheltered spot. A greenhouse gives a longer season, usually more fruit, and less exposure to blight.
Can I grow tomatoes indoors?
Only with plenty of light. Choose a small variety, give it your sunniest window plus a grow light, and tap the open flowers to pollinate them.
Why is my tomato flowering but not fruiting?
Usually temperature: fruit sets poorly when days go above about 32 °C (90 °F) or nights drop below about 13 °C (55 °F). Under cover, still air is the second cause.
Why are my tomatoes splitting?
Uneven watering. After a dry spell, heavy rain or a big watering makes the fruit take up water too fast and the skin cracks. Keep the soil evenly moist and mulch.
Should I remove tomato side shoots?
On cordon (indeterminate) varieties, yes. On bush (determinate) varieties, no: those shoots carry the crop.
How many tomatoes does one plant give?
A well-grown plant typically gives 2.75 to 5 kg (6 to 11 lb) of fruit over the season, depending on the variety and the summer.
Can tomatoes survive frost?
No. Frost damages or kills them. Plant out after your last frost and pick everything before the first.
Do tomatoes come back every year?
No. They are tender plants, grown as annuals and killed by the first frost. Sow or buy new plants each spring.
Related guides
Sources
- How to grow tomatoes (opens in a new tab) Royal Horticultural Society
- Tomato plant (opens in a new tab) ASPCA Animal Poison Control
- Growing tomatoes in home gardens (opens in a new tab) University of Minnesota Extension
- Tomato growing guide (opens in a new tab) Cornell University Cooperative Extension
- Growing tomatoes in the home garden (opens in a new tab) Iowa State University Extension and Outreach
- Blossom end rot (opens in a new tab) University of Wisconsin-Madison Extension
- How to grow tomatoes (opens in a new tab) BBC Gardeners’ World