What to Grow in a Greenhouse: A Seasonal Guide

Greenhouses are the perfect home for many of your garden plants, flowers and veggies. Whether it’s to facilitate growing in the first stage of their lives or as a permanent spot, greenhouses are a great way to add some colour and diversity to your garden.

However, getting the most out of your greenhouse requires a bit of seasonal planning, and it can get a bit overwhelming.

Not to worry, we have you covered. We’ve created a comprehensive, seasonal guide, suitable for beginners and keen gardeners alike, outlining what to grow in a greenhouse. Keep reading to find out what flowers, fruit and veg are easy to grow in a greenhouse throughout the year.

What to Grow in a Greenhouse in Spring

As the season of new life, spring is probably one of the busiest times of the year for greenhouse owners.

Early spring is prime time for sowing seeds for young, tender plants in a greenhouse, ready to be moved outside when it gets warmer. Around April, fast-growing crops like sweetcorn, courgette, squash and melon should all be sown in a greenhouse. Then, when it gets warmer, they can be transferred to their final growing places, either outside or under glass.

You can also sow basil seeds in early springtime, which can be grown inside your greenhouse or transplanted outside during the summer months.

The best way to grow tomatoes and peppers in a greenhouse is to sow them in a propagator in early spring. Or, if you have an unheated greenhouse, you can buy ready-grown pepper and tomato plants and introduce these to your greenhouse in mid-spring.

Top tip: If you want to incorporate some gorgeous garden flowers into your greenhouse, find out what flowers you can plant now and throughout the year in our seasonal guide.

What to Grow in a Greenhouse in Summer

In summer, while many of your spring planters will have been moved outside, plants that love humidity will continue to grow and thrive in your greenhouse. These include Mediterranean plants and veggies like tomatoes, peppers, chillies and cucumber.

Remember, while these plants enjoy the heat, they do need plenty of moisture in the soil to keep them producing veggies throughout the summer. Tomatoes also need support when they grow. Use a trellis or stake to keep them from sprawling or the stems snapping, or a stake to keep them from sprawling or the stems snapping.

If you want to grow fruits, summer is also a great time to plant strawberries or raspberries in hanging baskets or containers in your greenhouse. If you’re lucky enough to have a larger greenhouse, you could even grow lemon, lime, or orange trees, as these enjoy warm and stable temperatures that aren’t guaranteed outdoors during the British summer.

Outside your greenhouse, mid-summer is a good time to sow calabrese, French beans and parsley. These can then be brought inside in the autumn, once the summer crops have finished and been removed.

What to Grow in a Greenhouse in Autumn

Autumn is usually a relatively quiet time for greenhouse owners, but there are still a few plants that can make the most of the warmer indoor temperatures and autumn sun.

First, you should remove all spent summer crops.

You can plant lettuce seeds into beds or growbags where they can harvest over the summer and can also sow other hardy salads, like rocket, pak choi and spinach, into trays or pots of compost. Then, plant the seedlings into larger containers, border soil or grow bags.

You can also move herbs like mint, parsley and chives into pots and bring them into the greenhouse. Here, they’ll continue to grow over the autumn and winter.

What to Grow in a Greenhouse in Winter

Despite the cooler temperatures, you can still make good use of your greenhouse during winter.

The hardy vegetables and herbs that you plant in autumn can still grow effectively indoors over the winter. Remember to keep all vents and windows shut to trap the heat and prevent rain, or even snow, reaching your plants.

You can also sow broad beans and peas inside to over-winter, and plant them out in early spring when the clay soil is softer and more manageable. Similarly, late in the winter, hardy plants like Brussel sprouts, onions, cabbage and early leeks can be sown in the greenhouse and planted out later in the year when it gets warmer.