Growing Tomatoes in a Greenhouse

How to grow tomatoes in a greenhouse

We provide expert advice on growing tomatoes in a greenhouse – including how to tie in and water them.

A table displaying which months are best to sow, plant and harvest.
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
To do
To do

Do not To do in January

Do not To do in February

Do not To do in March

Do not To do in April

Do not To do in May

Do To do in June

Do To do in July

Do To do in August

Do not To do in September

Do not To do in October

Do not To do in November

Do not To do in December

Tomatoes will thrive in a greenhouse in midsummer with the right light, warmth, water and feed.

There’s no point in ruining your hard work by watching the plant collapse under its own weight, when some simple staking will save the day. Nor do you want too many leaves when it’s the precious fruits you want to savour.

The warm, humid conditions of a greenhouse are the perfect spot for growing basil – the ultimate flavour partner for tomatoes. Discover how to grow basil and tomatoes together, in the greenhouse.

For full advice on growing tomatoes, indoors and out, check our tomato grow guide.

Here are a few timely tips to keep your plants on track for a bumper harvest.

Removing sideshoots prevents the fruits being shaded by leaves.

You will need

  • Tomato plants
  • Tomato food
  • Watering can
  • Canes
  • String

Total time:

Step 1

The first job is to stake up any tomato plants before they collapse under the weight of their fruit. Drive a bamboo cane into the soil next to the plant, taking care not to damage the roots, then tie the stems to the cane with twine, using a figure-of-eight knot, in one or more places, depending on how much support is needed.


Step 2

Removing sideshoots prevents the fruits being shaded by leaves. It also diverts the plant’s energy into the growing fruit, making it more productive. Simply grasp the young shoot, emerging between main stem and fruiting branch, and bend it sharply downwards to give a clean break from the branch. Try not to leave a stump behind that will die back.


Step 3

As temperatures rise, keep watering your plants whenever you think they need it – daily or every other day, depending on the temperature. Misting flowers regularly will aid fruit set. Feed once a week with a high-potash fertiliser, to encourage the production of more flowers.


If your first attempt at pinching out sideshoots isn’t successful, nip out the remaining bit and remove it without damaging adjacent growth.