Growing Brussels sprouts

Brussels sprouts attract their fair share of pests. Here’s how to identify and control the important species.

The diamondback moth, cabbageworm, cabbage looper, flea beatle and aphid are five common pests of Brussels sprouts.

• The diamondback moth (Plutella xylostella) This is a particularly troublesome threat to Brussels sprouts due to its tolerance of many chemical insecticides. This pest is a small, greyish-brown, night-flying moth with a 2cm wingspan. It holds its wings together, roof-like over its back, when at rest. When in this position, a pattern of three diamond-shaped spots can be seen along the top of the moth’s body.

DISEASES IN BRUSSELS SPROUTS

Diseases that commonly affect Brussels sprouts are blackleg, black rot, downy mildew, Fusarium wilt and cabbage yellows. Many crop diseases can be prevented by practising crop rotation, using sterile starting mixes, and adopting strict sanitation methods.

Treating seeds in a hot water bath before sowing may help to control diseases such as black rot, blackleg and damping off.

The small caterpillars (up to 8cm long at maturity) are pointed at both ends and range in colour from cabbage green to yellow. When disturbed, the larva rapidly wiggles its body back and forth, often causing it to fall off the plant.