Are Greenhouses Good for Growing Vegetables?

Greenhouses have so many benefits for passionate gardeners, but possibly the very thing of all is using them to grow fruits and vegetables.

If you’re passionate about producing your own food at home then greenhouses can be fantastic for growing vegetables. 

Here are the very best reasons why greenhouses are brilliant for food production:


Longer Growing Season

Possibly the biggest reason why greenhouses are good for growing vegetables is that they greatly extend your growing season. This is especially so if you’re in a temperate climate like North America or the UK. 

Greenhouses warm up quickly in the spring, and they stay warm long into the fall. This means that you can start your vegetable plants much sooner and they will keep on cropping until much later in the year. 

From my own experience, as I write this article in February, my greenhouse is currently at 31’C / 38’F on a pleasant sunny day. And that’s when there’s snow on the ground across the rest of the garden. 

Yes, the temperature drops at night, but the plants in my greenhouse are already showing vigorous healthy green shoots while everything outside sits frozen and motionless waiting for April or even May before putting on a growth spurt.

The same happens at the end of the season. It’s not unusual for me to be harvesting tomatoes and peppers in September, October, even November in milder years. And that’s all thanks to them growing within the protection of my greenhouse. 

Put bluntly, if you want to grow as many vegetables as possible in a fixed amount of space then adding a greenhouse to your garden is one of the very best things you can do.

Warmer Temperatures

Greenhouses naturally trap the sun’s rays, and therefore become warmer than the outside temperature. This happens all year round, but it is most noticeable in summer when the sunlight is most intense. This provides opportunities not afforded to gardeners without a greenhouse.

One perfect example would be peppers, which can be difficult to grow outside in temperate regions. Or more correctly, it can be difficult to get ripe fruit to enjoy at the end of the season. Whether it’s hot chilli peppers or sweet peppers that are your thing, all forms require a long growing season and ideally high temperatures to thrive.

While it *is* possible to grow peppers outside in warmer years, and to receive *some* fruit, the results of growing them in a greenhouse are incomparable. 

Not only can you start your pepper seeds sooner, so they have a longer season to grow, but the higher temperatures also speed their flowering and fruiting. Even outdoor pepper plants can be brought into a greenhouse as the temperatures drop, thus ensuring as many ripe fruits as possible.

Of course this is just one such example, but there are many others. Melons, watermelons, cucumbers and tomatoes can all be grown outside successfully, but tend to do even better inside a warm, cosy greenhouse. 

Greater Range of Produce

The fact that more cold-sensitive plants will grow successfully inside a greenhouse means that you can grow a far wider range of crops than the non-greenhouse owner. 

Many colleagues of mine at work were shocked when I told them I was growing watermelons here in cold, drizzly Britain. And that’s just for starters. Others manage to grow more exotic produce like kiwis or passion fruits – again largely thanks to a well-positioned greenhouse. 

Easy Pest Control

Growing vegetables outside exposes them to an almost never-ending array of potential pests and problems. From damage caused by heavy rainfall through to being nibbled by caterpillars, birds and more. 

While it’s certainly possible to grow vegetables outside, it’s a lot easier to control the environment in a greenhouse. Not only can you control the temperature and watering more accurately, but pest control can become simpler. 

Firstly many pests like carrot fly and caterpillars are less likely to make their way into your greenhouse, but if pests do take up residence they tend to be easier to spot and to eliminate. 

Greenhouse pest control doesn’t necessarily have to involve chemicals either. Biological control, such as beneficial predatory nematode worms, are easy to apply inside a greenhouse and can help to keep pests at bay. 

Simple to Improve Soil

A small growing area makes it easier to offer the very best growing medium possible. For example those tomato plants can be sunk into big pots of rich compost. Or your greenhouse raised beds can be laden with organic, environmentally-friendly fertiliser. 

Just as importantly, being protected from summer rainfall means that nutrients are able to remain in the soil for longer, benefitting your plants, rather than being at risk of being washed away. 

All-Weather Gardening Opportunities 

One final benefit of growing vegetables in the greenhouse – at least for a fair-weather gardener like me – is that it means you’re no longer reliant on good weather. Even if the rain is falling in sheets you can remain dry and warm within your greenhouse.

For people who truly enjoy gardening, this is a fantastic addition to your gardening year. Finally you can tend your crops when you want, when you’ve got time available, rather than having to dodge around summer winds and rainfall.

This all-weather gardening also of course has an impact on the success of your vegetable growing too. It means you can keep an eye on your food plants regularly. No being stuck indoors for a week or two thanks to bad weather, while slugs and snails decimate your crops. Instead you can be daily contact with your plot, tending to the ever need of your plants.  

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