Greenhouse growing in Winter can be tricky as options are more limited. However, even in the cold Winter months it is possible to continue to enjoy growing in your greenhouse. There are a variety of flowers and vegetables that are tough enough to withstand the frosty nights, and if your greenhouse is heated the list is almost endless.
When we have the darker nights (and days), gardening is a great way to stay active, even for just a few minutes a day, which can help lift your mood. Sow some seeds, to reap the rewards during Spring and Summer, giving you healthy, nutritious crops or beautiful flowers to look forward to.
Winter vegetables to sow or grow in the greenhouse
The RHS have a number of articles on vegetable to grow in the greenhouse in winter. Here are some ideas:
Usually sown in late Winter through to late Spring in batches a few weeks apart, for several batches throughout Summer. Broad beans are an easy and productive crop producing early harvests and needing little maintenance.
Brussel sprouts take around three months to grow, so harvest them in March when they are roughly 1-2″ in diameter. Sprouts are good for freezing too if you have a bumper crop!
Sow small batches of different varieties and you enjoy harvests all year round. Cabbages are a good source of antioxidants, vitamins and are full of fibre giving you a delicious, healthy vegetable.
A sweet, tasty, versatile vegetable, carrots are a well known, well used kitchen favourite. Carrots are an ideal vegetable to grow as they don’t take up much space and can be grown in containers if required. If you sow several batches regularly, you can enjoy harvests almost all year round.
Cauliflower is a little more challenging to grow in the UK as some other vegetables, but it is possible. Sow seeds very early in the year in your greenhouse ready for harvesting in around 5 months.
Parsley, coriander, sage, thyme, rosemary and tarragon are all herbs that will continue to thrive in a greenhouse during Winter. Or plant seeds for new plants to enjoy throughout the year. Herbs give off a great smell and are a delicious addition to many culinary creations.
Lettuce grows fairly quickly, sow seeds early in the year and harvest the leaves once they get big enough to use.
The perfect Winter ingredient, potatoes started early in the Winter season will be ready to enjoy by March.
Spinach and Kale
Spinach seeds can be sown in January for a harvest around April. Or it will continue to grow through Winter. Spinach is full of nutrients and high in fibre and iron. It freezes well and can be added to all sorts of dishes including curry, fish pie or as a side dish. Kale is frost hardy and can survive in temperatures as low as -6C.
Flowers to sow or grow in the Winter
Get ahead of the game and sow begonia seeds early in the year for healthy, strong, colourful flowers to bring life to your pots and hanging baskets. This is a far more cost effective way of bringing life to your garden than having to spend on fully grown plants.
Chrysanthemums are a vibrant, colourful flower that will look great in your hanging baskets or pots. They aren’t frost hardy so keep the plants in your greenhouse before planting outside until the last frost has been and gone.
Dahlia seeds should be sown around February ready for vibrant colour in your garden throughout Summer. They also need a frost free place for Winter storage.
Plant Dianthus seeds mid January to April in your greenhouse and keep under glass until they have reached 4″tall, they can be planted outside once any risk of frost has passed. Bring your plants back in to your greenhouse for overwintering.
Geraniums seeds should be sown between October and March and kept frost free by being put back in your greenhouse for Winter.
Sow lobelia seeds from late Winter until mid Spring in your greenhouse for beautiful flowers throughout Summer. Again, bring your lobelia plants in to your greenhouse over Winter to protect them and enjoy them again the following year.
Caring for your greenhouse plants
Ensure your greenhouse is clean – if greenhouse growing in winter your plants will need as much light as possible so, keep the glass clean for optimum benefit of the shorter daylight hours. Your plants will need a lot less water, if any, so check the soil is dry before adding any. You can provide extra insulation using horticultural bubble wrap, and it is also possible to heat a greenhouse with a tealight in a terracotta pot. Bear in mind that whilst your plants may start off as tiny seedlings, they will grow, so consider how much space they will need especially if planting in containers. On bright, warmer wintry days, open the doors of your greenhouse as early as possible and close them before sun set to provide ventilation to your plants. Always use a good quality soil, your plants will thank you for it!