Brassicas are a fantastic family of crops, with varieties including cabbages, cauliflowers, broccoli, turnips, kale and Brussels sprouts.
Brassicas share some common characteristics, including the soil they like, the food they need and their ideal location.
The right soil for brassicas
Brassicas favour a soil that is neutral to alkaline in pH rating.
- Before planting brassicas, use a simple soil testing pH kit to work out how alkaline your soil is.
- If needed, you can increase the alkalinity by adding lime to the soil. Brassicas will then perform much better and be less susceptible to disease.
Avoid growing brassicas in the same place
- If you plant brassica crops in the same place year after year, there’s an increased risk of soil-borne pests and disease spreading.
- Club root, which causes discolouring and wilted leaves, and chafer grubs are two problems which can be reduced by rotating crops in different spots around your garden or allotment.
Preparing your soil
- Prepare the soil a few months before crops go in, leaving the surface time to settle and firm up.
- Leafy brassicas, such as cabbage and kale, do better with access to nitrogen and nitrates in the soil.
- Put easy-grow nitrogen-fixing plants, such as peas and beans, in the ground the year before you plan to plant brassicas as this will naturally boost the nitrogen in the planting area.
How to feed brassicas
When you prepare the soil the season before, dig in plenty of organic matter such as compost and manure to improve the soil texture and boost nutrient levels. General-purpose fertiliser can also be added while digging in.
Just after planting, give the soil a layer of mulch, such as leaf mould, garden compost and well-rotted manure, to act as a feed and to keep moisture in the soil.
Don’t let brassica plants come into direct contact with the mulch, though - leave a little space around the plants. This so the base does not get too soggy and go soft and rot.
Most brassicas only need watering when you’re planting them and when the ground is dry; apply a liquid feed as your brassica’s heads start maturing on cabbages and cauliflowers.
Use a sharp knife to cut your brassicas at the base when harvesting so as not to damage the plant itself.
How to protect brassicas
Try to grow crops like Brussels sprouts, cauliflowers and cabbages away from areas exposed to wind and near to a natural windbreak, such as a hedge. You can also buy mesh and poles and make a protective barrier around your crops. Use bamboo canes to support tall growing brassicas like Brussels Sprouts to support and protect them from the wind. Brassica collars are also an effective line of defence when it comes to protecting your crops. Simply place around the base of young plants to protect them from pests like the cabbage root fly.