How to grow brassicas

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’s 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.

Getting good soil density

Brassicas like compact and firm soil to grow in, with plants well anchored in the ground.

  • Prepare the soil a few months before crops go in, leaving the surface time to settle and consolidate.
  • 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.

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.

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.

How to protect brassicas

Try to grow crops like sprouts, cauliflowers and cabbages away from areas exposed to wind and near to a natural windbreak, such as a hedge. Strong winds can cause a lot of damage to these types of brassica.