How to grow successful brassicas

Brassicas, like kale, cauliflower, cabbage and broccoli, have the ability to frustrate the novice gardener but they are good growers once you get the basics right.

Brassicas (veg plants from the mustard family, which include cabbages, kales, cauliflower and broccoli) need a little extra attention when they are planted out to keep them protected from pests. If you get it right at this stage, you’ll be much more likely to get a fab crop. If you don’t, then you’ll be most likely to experience at least one of the three most common problems: Cabbage root fly, caterpillars or pigeons. Trust us, it doesn’t take long to put up these two simple defences and it’s well worth doing.

Set down a 'brassica collar' around each plant

This is done to protect brassica plants from Cabbage Root Fly. These flies are attracted by the smell of the brassicas and will lay their eggs at the base of the plants. When the eggs hatch, the larvae crawl underground and feed on the roots of the plant, causing it to wilt and eventually die. By positioning a ‘brassica collar’ around the base of each plant, you can prevent the hatched larvae from reaching the roots. Cut out a 15cm circle from some of the cardboard packaging that you’ll receive your plants in (we’d recommend using an old CD as a template – much easier!) Cut a straight line into the centre. Cut another 2 or three short slits (1-2cm) out from the centre so that there is a bit of give as you wrap the cardboard disc around the stem at the base of the plant.

Protect your brassicas with a netted tunnel cloche

Netting or horticultural fleece can be used to create a barrier against butterflies, moths and pigeons. Butterflies and moths are attracted to the scent of brassicas and will lay their eggs in vast numbers, often on the underside of leaves where they’re not so easy to spot. When the caterpillars hatch they can quickly cause a lot of damage. Pigeons are even worse, and you can visit the veg patch one morning to find they’ve eaten the whole lot!

The easiest thing to do is build a tunnel cloche to go over the row – it will need to be about 80cm high minimum. Cover it with a tight mesh netting so that butterflies can’t fly through. Alternatively, you could simply drape horticultural fleece or insect proof netting over rows, secured at the corners and edges with stones. If you want to prop up the netting/fleece so that your brassicas have more growing space, stick a few bamboo canes into the bed with upturned jars on top and use this to hold the netting up.