If you have a polytunnel garden, you can have cabbage varieties available to eat all year round. One option is to grow perennial brassicas that will remain in your growing areas for several years. But a more traditional approach is to sow seasonally throughout the year so that you have cabbages and members of the same plant family to eat all year round.
Growing annual cabbages can work well if you have a small polytunnel and want to implement a crop rotation plan for your annual crops. It can be challenging to work around perennial plants. So if you have mostly annual crops, which cabbage varieties should you choose?
You might not have planned ahead for cabbages over the winter. But you can still sow now for cabbages in the spring. Here are some of the cabbage varieties that you could consider:
Durham early is one of the best known and most reliable cabbages that are sown in late summer/ early autumn for harvesting in the spring. This variety has firm, well-flavoured, pointed hearts on compact plants. It can be sown with narrower spacing for ‘spring greens’ that will be ready to harvest from around February or March next year. Or spaced out a little for larger, hearted cabbages.
This is another very reliable spring cabbage option. This is another traditional option for those who want to sow in autumn and reap the harvest in the spring. Also known as ‘sweet heart cabbage’ this is an old English variety well known for its reliability for overwintering. It was bred by George Wheeler of Warminster in Wiltshire in around 1844. It can also be used for spring greens or hearted cabbages and will mature fully in around 240 days.
This dark green open-headed cabbage is another great option for overwintering and for spring greens. In fact, the spring greens can be ready for harvesting from as early as January. It can be sown as late as September, though is usually sown in August for transplantation in September or October. This is also available in organic seed, which can be rare for spring cabbages.
April is another spring cabbage variety to consider. It too matures and can be harvested in late winter/ early spring. The heads of this variety are pleasingly compact, on dwarf plants. It can be a great choice where space is limited (such as in a typical domestic polytunnel) because it can be planted at 30cm spacings as it makes few outer leaves. While best sown in July or August, it can still be sown in your polytunnel this month.
This FI hybrid spring cabbage is another interesting option to consider. It is a very versatile option which can be sown to provide spring greens or medium-sized hearted spring cabbages. And it can also be sown at different times throughout the year for summer and autumn crops. It is very winter hardy and can outperform many non FI varieties. Sow it this month or next for overwintering.Space to around 15cm apart for spring greens, then take every second plant in March to allow the rest to continue to mature.
Chinese Cabbages/ Pak Choi
In addition to considering these more typical spring cabbage options, you could also consider growing Chinese cabbages and other Asian greens for ‘spring greens’. There are an interesting range of different Chinese cabbages and related brassica plants to consider.
Planting Cabbage Varieties to Avoid the Hungry Gap
Planting in late summer and autumn for spring greens is a great way to get a jump start on the season next year. Traditionally, gardeners would experience what became known as the ‘Hungry Gap’. This was a period after the produce stored over winter began to run out, but before spring sown crops were ready to harvest. A polytunnel allows you to avoid a hungry gap altogether.
Cabbages sown at this time of year will have the chance to begin growing before the cold weather arrives. And in a frost-free polytunnel, your overwintering cabbages will survive no problem at all. When grown outside, certain cabbages can be damaged by frost or other extreme weather conditions. But in a polytunnel, there should be no such issues. The cabbages will remain largely dormant over the coldest months, but then spring back into active growth again once the weather begins to warm.
Developing strategies to avoid the hungry gap and be able to grow and harvest food year-round is one of the key concerns of polytunnel gardening. Planting spring cabbages is one way to meet your goals.
Tips for Success with Overwintering Cabbage Varieties
If you are planting overwintering cabbages, we strongly suggest that you do not direct sow. It is far easier and you are more likely to succeed if you sow in modules or seed trays and then transplant seedlings to your growing areas. Apart from anything else, seeds and very small seedlings can be very vulnerable to pests such as slugs and mice at this time of year.
Another thing to remember is that cabbages, like other brassicas, are nitrogen hungry plants. It is important to make sure that you are planting them into growing areas that are fertile and rich in nitrogen and other important plant nutrients.
If you are sowing overwintering leafy crops into beds that were in use over the summer months, top dress the area with a good quality compost or other organic mulch before planting.
It is also a good idea to consider sowing spring cabbages and other leafy winter greens into beds vacated by leguminous plants (beans or peas) that have been fixing nitrogen over the summer months.
Another thing you could try is growing cabbages for winter polytunnel growing alongside overwintering broad beans. This won’t help in giving the cabbages the nitrogen they need (since nitrogen fixation won’t restart until spring), but could help avoid depleting nitrogen in the system and mean you can sow other plants in the area come late spring/summer with less further amendment.
Protecting Cabbage Varieties Over Winter
A polytunnel will give protection from certain common pests that can decimate a brassica crop (such as pigeons for example). But extra cloche protection could be a good idea, depending on the pests you encounter in your area. You may find that slugs or rodents are an issue. If so, placing barriers around your young cabbage plants can be a good idea. You could consider using household rubbish like plastic bottles or old milk containers for the purpose.
Are you growing cabbages in your polytunnel this winter? What are your tips? Which cabbage varieties do you like to grow? Let us know in the comments below.
Elizabeth Waddington is a writer and green living consultant living in Scotland. Permaculture and sustainability are at the heart of everything she does, from designing gardens and farms around the world, to inspiring and facilitating positive change for small companies and individuals.
She also works on her own property, where she grows fruit and vegetables, keeps chickens and is working on the eco-renovation of an old stone barn.
To get in touch, visit https://ewspconsultancy.com.