Growing tomatoes in a greenhouse

UK Home Improvement

Growing Tomatoes in a Greenhouse

February is upon us. If you’re a tomato lover and want to grow your own, now is the time to plant them in the greenhouse. The good thing about growing them in a greenhouse is that you can control temperature and moisture levels so your plants stay healthy throughout the growing season.

You can monitor temperature, humidity and light levels carefully so that everything is perfect for your plants.

At this time of year there is plenty of sunlight available and temperatures are still fairly cool (under 21 degrees celsius). 

Tomatoes need lots of light in order to grow properly so make sure they get at least six hours per day under direct sunlight if possible.

Install a Trellis System

The most important thing you can do is choose a trellis system that’s easy to install and remove. Tomatoes tend to be heavy, so they’ll need something sturdy enough not to break under their weight.

Different varieties need different supports, so check the seed packet or plant label to see which variety you are growing.

Cordon tomatoes are tall, single-stemmed plants. These will need tall supports. Side-shoots should be removed regularly. Bush tomatoes may not need support, depending on how heavy they get. Side-shoots should not be removed.

Bush tomatoes are great in pots, or other planters such as a Vegtrug.

Trellises are also useful because they allow for more efficient use of space. If you’re setting up your greenhouse for growing tall tomato varieties, consider getting two or three different types of trellises so that when one gets full-grown, another can be added on top.

The best time to start tomato plants in a greenhouse is when the temperature outside is around 18. This will give you plenty of time for them to grow strong roots.

Finally comes training them up their trellis: simply hold onto one side while gently pulling upwards until there are no more leaves left hanging down low enough for pests such as slugs or snails who might try eating them. Then tie off those loose ends securely using twine.

Watering Your Tomatoes

Tomatoes need consistent water levels otherwise they can split or suffer blossom end rot. The amount of water your tomato plants need depends on the soil type you’re using. Sandy soil dries out quickly, while clay tends to retain water for longer periods of time. Tomatoes need a steady supply of moisture throughout their growing cycle – and if you’re growing them in containers, it can be difficult to know when they need watering or how much they’ll drink up at once. To keep track of this, make sure that you check the moisture level in your pots every day or two by sticking your finger into the soil (you should feel cool about 6 inches down). If it feels dry, or if there’s no moisture at all, add some water until everything feels moist again.

And Don’t Forget…

In a greenhouse environment, you should encourage the pollination of your tomato plants by opening the vents regularly to give pollinating insects access to the flowers. Pollinating is essential for the fruits to grow and in creating the next lot of plants.

You can also lightly tap or shake the flowers when they’re fully open to help pollen transfer within the flower. Misting your tomato plant’s flowers with water may also help the pollination process.

To harvest your tomatoes just cut them off carefully with sharp kitchen scissors. A ripe tomato will be red and plump with seeds, while an under-ripe one will be greenish in colour with few seeds.

Final Thoughts

Tomatoes are one of the most popular vegetables in the world, and for good reason. They’re delicious, nutritious and easy to grow. If you have a greenhouse at home or work, you can easily add tomatoes to your menu by planting them in late February. Keep them watered and fed with a fertiliser and you’ll have fresh tomatoes all season.


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