Late spring is the time for starting off tomatoes in an unheated greenhouse and if you are buying plants, look for sturdy, smaller ones rather than tall, leggy specimens.

Most greenhouse tomatoes are tall, so will need support. If you are growing them in pots you can stake them with canes, but that will be trickier if they are in gro-bags. Instead, tie strings to the greenhouse roof above the plants and drop the string down to the plant, tying it loosely around the stem. Then, as it grows it can be gently twisted around the string.

Greenhouse tomatoes are usually restricted to one stem, so remove all sideshoots as they appear, lightly shaking the plants daily to encourage pollination.

When the fruits form, feed regularly with tomato feed, water religiously and then, when the fruits start to ripen, remove lower leaves to allow the sun to do its work on the fruit.