Tomatoes are well worth growing because of the high yield - an average of six trusses could give between 15 and 18 pounds of fruit depending on variety. But an even better reason is the flavour.
Commercial crops are picked under ripe for transportation purposes and flavour inevitably suffers. The tomato you grow yourself can be picked when perfectly ripe. It’s also one of the few crops capable of giving months of food for little effort.
When to plant tomatoes
The easiest sowing time to grow tomatoes from seed for most gardeners is late February or early March.
Young plants are ready to go into the garden when the first truss of flowers has appeared and there is no risk of frost – usually from mid-May to early June.
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Where to plant tomatoes
Tomatoes are subtropical plants and they need sun, moisture and warmth but you don't need a tunnel or greenhouse.
If growing tomatoes outside choose a sunny, sheltered spot.
Tomatoes grown outside simply crop later and are more prone to going down with potato blight (Phytophthora infestans) so try to keep your tomatoes and potatoes apart.
Bush varieties of tomato plants can be grown in grow bags, containers and hanging baskets.
How to grow tomato plants
Sow seeds thinly into small, round, plastic pots filled with soil-less seed-sowing compost. Lightly cover and place somewhere warm - a heated propagator is ideal but a warm windowsill will also do.
When the seedlings reach an inch high and show more than two leaves, transplant them into individual pots - handling them by their long narrow leaves. Immerse them deeply in the compost to encourage better roots.
Once the plants reach six - eight inches in height (up to 20 cm) transplant them either into the greenhouse or into larger pots.
Buy healthy plants and avoid any that look stunted or a very dark-green in colour as these have been subjected to cold nights.
Avoid heritage varieties unless you live in the warmer south-east. Generally they fail to do well in many parts of the country.
Young tomato plants you have grown from seed or bought as plugs need to be kept warm at night and horticultural fleece helps greatly.
Tomatoes are frost tender and they must not go outside until mid-May at the earliest. But plants could go in an unheated greenhouse at the end of April - again use fleece if it’s cold.
Dig a hole twice the depth of the pot - push a 6ft cane (or a square tree stake) into the ground next to the hole to support the plant.
Pop the tomato plant in the hole and plant deeply, allowing the soil to come up to the level of the rounded seed leaves near the base. This will encourage new roots to form and keep the tomato well anchored.
Once planted, water sparingly at first until the first truss (group of flowers) appears. This encourages a deeper root system.
Grow bags, hanging baskets and containers
Tomatoes can do well in hanging baskets, grow bags and containers in warm summers but you need to find a sheltered position in good sun.
Bush varieties, which give small cherry fruits, are perfect for growing in grow bags. They are sometimes less baffling for beginners as the plants do not need the side shoots pinching out. But care must be taken to keep the fruit off the ground as tomatoes are prone to slug damage and some varieties take up a lot of ground space.
Cherry tomatoes, such as Tumbling Tom, are ideal for growing in baskets and can easily be kept off the ground and out of the way of slugs and snails.
Up to three plants can be raised in a growing bag. First prepare the bag by shaking and kneading to break up any lumps, then form it into a hummock shape. Puncture the base a few times to make some drainage holes and cut out the three pre-marked planting squares. Scoop out compost for the tomatoes to be planted.
The top of the root ball should be beneath the top of the bag and have a covering of compost. Firm in and water.
To keep plants steady, put a growing bag frame over the bag and insert a cane next to each plant.
Single tomato plants are perfect in large (30cm) pots filled with a mixture of John Innes No.2 compost and multi-purpose compost.
Feeding and caring for tomato plants
Once the first truss appears step up the watering, feed with a specialist potash-rich tomato food every two weeks and pick out any side shoots. Finally restrict the plant to six trusses - making sure that your plants have sufficient support to bear the weight of fruit. Thick bamboo canes do the job well.
If you are using the same greenhouse, the soil must be changed every other year to avoid soil sickness. Dig out the old bed and replace with compost-rich material.
During the growing season, tomatoes will need watering daily or twice a day in hot, sunny or windy weather.
It’s important that plants never completely dry out as an irregular water supply can lead to blossom end rot, a common problem recognisable by fruit forming a hard, flat black patch.
Visit our tomato recipe section for ideas on using tomatoes in the kitchen
Pinching out tomato side shoots
Snap out shoots that grow in leaf joints with your thumb and forefinger - side shoots steal water and nutrients from the plant, preventing it from putting its energy into producing fruit.
Strip leaves from under the first truss of fruit (at the bottom of the plant) when the tiny tomatoes appear. This will allow air and light to reach them, keeping plants healthy and improving the quality of the fruit.
There’s no need to remove leaves from under the other trusses, although you can snip off any that are yellowing.
When your plant has produced four sets of trusses, pinch out its growing tip. This will ensure all of its energy goes into producing fruit. However, if you are growing a multi-stemmed bush tomato, these do not need side shooting. Only pinch the tips to keep plants tidy and within bounds.
Commercial growers never cut leaves, side shoots or trusses with a blade when harvesting because the cut edges bleed and weaken the plant and possibly allow botrytis to develop. The torn edges leave a scar but dry faster and are safer.
Pests and diseases
Tomatoes can get virus infections and these too can be fatal. Symptoms are usually yellowing or mottling of the leaves and reduced yield. Break off badly affected leaves.
Is blight a risk to tomatoes?
Luckily some varieties resist blight. 'Ferline', an F1 hybrid, has fared well in outdoor trials and this heavy-yielding, red-fruiting variety is vigorous. 'Koralik', an Eastern European variety, also shrugged off the disease in trials. Grafted tomato plants avoid many soil-borne fungal diseases and viruses and it's the first year home gardeners have been able to buy them.
Grafted tomato plants
Grafted tomato plants have been used by commercial growers for many years, but now the home gardener can also buy them too. Although they can cost an average of £10.00 for three plants the rootstock encourages greater vigour and your plants will crop earlier and more heavily - so the extra cost should be worth it. More importantly, the tomatoes aren’t affected by any seed-borne diseases.
Grafted tomato varieties
- 'Elegance' - a standard red
- 'Santorange' - an orange plum
- 'Conchita' - a red cherry
- 'Belriccio' - a red beefsteak
- 'Dasher' - a mini plum
Blight-resistant tomato varieties
Tomato 'Koralik' is a heritage Russian bush variety that crops early enough to avoid the main August wave of blight. But it has also shown good tolerance to blight in three years of trials throughout the whole season. The foliage has remained healthy, the yield has been consistently high and all the small, bright-red tomatoes on each truss ripen together.
'Premio' is another disease-resistant tomato which has been extensively trialled and this also should be suitable for outdoor use. The flavour is excellent and the handsome red fruit has shiny red skin so it looks good on the vine. It ripens well and evenly and the taste is outstanding. It shows high resistance to many tomato plant diseases making it perfect for the home gardener.
Commonly available cordon tomato varieties
These are restricted to six trusses and all the side shoots (the leafy growths in the gap between stem and leaf) are pinched out to develop an upright plant - this takes up less space and allows fruit to ripen easily.
Small orange fruits, exceptionally sweet. Crops well. For greenhouse or outdoor culture.
Excellent flavour, medium-sized round, red tomato with thin skin. Free-fruiting - one of my favourites.
'Gardener's Delight' AGM
Small, cherry-sized, bright red fruits with authentic, old-fashioned flavour. Grow outdoors or in the greenhouse.
Early-maturing, heavy-cropping F1 variety for cold or slightly heated greenhouses with excellent quality fruit. Recommended for growbag culture with an open growing habit and resistance to TMV, Cladosporium ABC and Fusarium 1 and 2. Fleshy fruit popular with vegetable exhibitors.
A popular and reliable plant that remains a favourite.
Golden-yellow, medium-sized fruit of excellent and distinctive flavour. Ideal for greenhouse or outdoor growing.
'Sweet Million' AGM
A heavy yielding plant that produces sweet, round cherry tomatoes.
As the name suggests this is a very sweet variety that produces lots of small, red cherry tomatoes on each truss.
Tomato bush varieties
Tomato bushes are the easiest for a beginner to grow and are ideal for containers and grow bags.
Very early with exceptional flavourful, one-inch wide red fruits.
Thick fleshed, nearly seedless plum tomato for sauces, ketchup, tomato juice and soup. Disease resistant and heavy cropping - for outdoors or greenhouse use.
'Tumbling Tom Yellow' and 'Tumbling Tom Red'
Sweet yellow or red, cherry-sized fruits that trail over baskets. Both are very flavourful.
A small specialty tomato grown that has been grown on the slopes of Vesuvias for hundreds of years. From the heirloom San Marzano.
Nutritional benefits of tomatoes
Tomatoes are packed with antioxidants and are rich in Vitamins A and C and lycopene, all helping to stimulate your body’s immune system. Cooked tomatoes deliver more health-giving lycopene.
Visit our fruit and vegetable section for more growing guides
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