Focus on... Glasshouse tomatoes

Make this your year for the tastiest indoor tomatoes! Growing under cover is reliable, fun and much easier than you think

- Lucy Chamberlain

IF you’re lucky enough to have a greenhouse, chances are it’s full of tangy tomatoes all summer. Not only a salad and sauce essential, tomatoes are also packed with lycopene, which is known to help fight cancer and heart disease. My retired smallholder parents grew thousands of glasshouse tomatoes each year, and this is where I cut my horticultural teeth. Now is the time to sow to ensure success with tomatoes, so how do you ensure bumper crops?

Although you can buy plants from garden centres, many of us sow toms because it offers the widest selection of varieties. Germination is strong and swift: sow eight-ten seeds on the surface of a 3 1⁄2 in (9cm) pot of well-watered seed compost, top with vermiculite and place in a well-lit propagator at 18-22°C (64-72°F). Multi-directional light is vital to deter leggy growth.

Prick out into individual pots once 2 1⁄2in (6cm) tall, positioning these at ever increasing spacings in a 15°C (59°F) spot. As they grew taller, space them out more (to deter legginess) then, as soon as the first flower truss appears, the toms can be planted into the greenhouse earth. This was my parents’ trump card – many growers would use hydroponics, but soil cultivation does give a better flavour.

More vigorous ‘grafted’ plants are available, boasting bigger yields (up to 75%) and improved disease resistance via a supercharged root system. These may come at a price, though (often £5 per plant), so I still primarily sow seeds. You can ensure a bumper root system by growing in the greenhouse border (my parents’ preferred method) or large tubs or ‘planter’ growing bags.