How To Grow Tomatoes From Seed

How To Grow Tomatoes From Seed
One of the most popular garden vegetables - and not surprising since the taste of fresh tomatoes from the vine is divine. There are numerous varieties from the small-fruited cherry types to the monster beefsteak forms; from the standard red to yellow, orange, green, purple and striped; from the standard tall cordon varieties to bush and even hanging basket types. Although growing-bags are the favoured growing medium, the plants take a lot more careful looking after than those growing in pots or in the ground. Outdoor tomatoes are well worth growing.

Sowing
Sow tomato seeds at 65°F (18°C) in seed trays or small pots and prick out into 3.5in (9cm) pots when two true leaves have formed. For greenhouse cultivation, tomato seeds can be sown from mid- January to early February (heated greenhouse) or late February to mid-March (unheated greenhouse). For outdoor cultivation sow tomato seeds in late March to early April.

Growing
Transfer to 9in (23cm) pots, growing-bags or plant 18-24in (45-60cm) apart outside when the flowers of the first truss are beginning to open; plants for growing outdoors should be hardened off first. Tie the main stem to a vertical bamboo cane or wind it up a well-anchored but slack sturdy string. Remove the side shoots regularly when they are about one inch 2.5cm) long. Some varieties are grown as bushes requiring no pinching out of side shoots and no support; Marmande AGM is grown as a bush but does need support.

Water regularly to keep the soil evenly moist. For best results we recommend feeding tomato plants every 10-14 days with a balanced liquid fertiliser, changing to a high potash one once the first fruits start to set. Remove yellowing leaves below developing fruit trusses. Once the plants reach the top of the greenhouse or have set seven trusses indoors or four trusses outdoors remove the growing point of the main stem at two leaves above the top truss.

Harvesting
Start picking when the fruit is ripe and fully coloured. At the end of the growing season lift the plants with unripe fruit and either lay them on straw under cloches or hang them in a cool shed to aid ripening. Or you can pick the green fruit and store in a drawer next to a banana.

Pim Dickson

Plant Expert

When Pim joined D.T. Brown, it was originally as a seed buyer, but now as our planting & sowing expert, he’s responsible for all horticultural and technical content, sharing his expertise in this catalogue, and through the growing advice and tips on our seed packets.

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