How to
Grow Tomatoes

Tomatoes come in a range of different shapes and sizes, and have different uses in the kitchen.

• Bite-sized cherry tomatoes are great for snacks and lunchboxes.
• Plum tomatoes are oval in shape with few seeds, ideal for cooking.
• Salad tomatoes are the most common type, medium-sized, round and very versatile.
• Giant beefsteak tomatoes are prized for their juiciness and flavour.

Tomato plants are also grouped into cordon and bush types. Cordon type tomatoes (sometimes called indeterminate or vine tomatoes) grow tall and upright, producing a single main stem with sideshoots growing from it. Bush tomatoes (sometimes called determinate tomatoes) grow into low bushes with many sideshoots.

Bush tomatoes need much less training than cordon types, so they’re a good choice for first-time tomato growers.

Tomatoes grow well in a greenhouse or outside in a sheltered, sunny spot. They appreciate a fertile soil, so dig in compost or well-rotted farmyard manure before planting. If you are short on space, you can even grow tomatoes in pots on a sunny patio or balcony.

Tomatoes are easy to grow from seed, provided you have somewhere warm and sunny to sow them. A heated greenhouse is ideal, but you can also sow tomato seeds in pots on a sunny windowsill.

1. Sow tomato seeds indoors from late February to early April. Sow the seeds thinly in seed trays filled with compost, and cover lightly with a 1cm (1/4in) layer of compost.
2. Water the trays and cover with clingfilm to create a humid environment.
3. Place the trays somewhere warm, such as a heated greenhouse or sunny windowsill.
4. Remove the clingfilm once the seeds have germinated. Keep the compost moist.
5. When the seedlings have two true leaves, gently ease them out of the compost, using a dibber and holding each plant by its leaves, not its stem. Transplant into 9cm pots filled with multipurpose compost and place in a warm, bright position to grow on.
6. Once the plants are around 15cm (6in) tall, they are big enough to be planted into their final positions, but wait until all risk of frost is past before planting outdoors.
7. Harden off plants for two weeks before planting outside, by placing the seedlings in their pots outside each day and moving them back inside each night.
8. Plant into pots, tomato grow bags, greenhouse borders or in the ground in a sheltered sunny spot. When planting cordon types, put the stakes in at the same time, so as not to disturb the plants’ roots later on.

You can also buy young tomato plants in spring and grow them on indoors until the weather is warm enough to plant them outside. Harden them off before planting out, in the same way as for seed-grown tomatoes.

Water the plants regularly, especially once the fruits start to form, keeping the soil moisture level as consistent as possible. Dry periods followed by overwatering can cause the fruits to take up too much water and split.

Once the fruits start to appear, feed pot-grown plants fortnightly with a high potash tomato food.

Tie cordon tomatoes back to strong support canes as they grow. Inspect the plants regularly and pinch out (remove) the small leafy shoots that appear at the points where the sideshoots join the main stem.

Once the plants have produced five trusses of fruit, pinch out the growing tips of the plants two leaves above the highest truss. This allows the plants to focus all their energy on producing fruit rather than additional foliage.

Bush tomatoes need no pinching out, but very heavily laden stems may need some additional support.

If you are growing tomatoes in a heated greenhouse, they should be ready to harvest towards the end of June. Outdoor-grown tomatoes will be ready later, towards the end of July. To test for ripeness, check the colour and squeeze gently. Ripe tomatoes are slightly tender to the touch but not soft.

There are a few pests and diseases to watch out for when growing tomatoes:

• Blight is a fungal disease that attacks the whole plant. The first signs of blight are chocolate-brown patches on the leaves and fruit. Remove any affected plants immediately and burn or dispose of them (but not on your compost heap). To reduce the risk of blight, plant blight-resistant varieties, and when watering, water the soil around the plant, not the leaves. Greenhouse-grown tomatoes are less prone to blight.
• Aphids suck the sap of young shoots and can stunt plant growth and transmit diseases. Stop infestations early by wiping the bugs off plants with a damp cloth. If you plan to use an insecticide spray, check that it is suitable for use on edible plants, and don’t spray when plants are in flower as this can harm bees. Planting French marigolds near your tomatoes can help, as the scent deters aphids.
• Blossom end rot is caused by calcium deficiency, and results in dark sunken areas at the base of the tomato. It tends to happen when plants are not watered regularly and are not able to take up calcium from the soil. Regular watering will usually resolve the problem, although affected fruits may have to be discarded.