Cabbage Patch Aphids

A few weeks back I was happily inspecting the cabbages, kale and broccolis in the office garden. ‘Flip, they’re looking good,’ I thought. Then I noticed one that was wilting a little. I took a closer look and there, nestling into the crevices around the growing tip I could see the tell-tale grey patches of cabbage aphid colonies. And I knew that if we didn’t treat it quickly, every one of our beautiful brassicas would soon be heading the same way.

Cabbage aphids specialise in the infection of brassicas (the cabbage family), and because the adults can develop wings they can fly in from a neighbouring garden. As soon as there is a healthy population on a single plant, winged adults emerge and spread to other plants, quickly leading to the little blighters overrunning your garden. Babies reach reproductive age in just 8 – 10 days, so numbers grow exponentially.

Identification: Cabbage aphids are small, grey, waxy insects that form large colonies on the leaves of their host plants. The indications: Wilting growing points, rolling/curled leaves and white lesions are all common indicators of a cabbage aphid infestation.

The danger: Cabbage aphids can physically damage and deform plants, especially the growing tips. More importantly, they are vectors for a number of diseases, and because they fly from plant to plant to establish new colonies they can spread these diseases across your garden quite quickly.

The solution: Diligence is key. If you spot a single plant that is infected, pull it out and destroy it. You can spray with an approved product, but be sure to get into the growing points and curled leaves. We always try to use the eco-friendly options such as Margaret Roberts Organic Insecticide or Efekto Eco Insect Control. Some predatory insects (ladybirds and wasps, for example) will predate on cabbage aphids, but they won’t be able to get rid of a serious infection. If they get started early the predators can keep aphid numbers down though.

When: Now! Autumn is usually when these little pests become most active, so inspect your plants daily.