Ladybirds on the Fennel (gouache style)

Ladybirds are small beetles, and their bright colours are a warning: if they're picked up, they release a bitter yellow fluid from their leg joints. The seven-spot, red with seven black spots, is the most familiar British species. Their larvae look nothing like the adults. They're long, dark grey and bristly, usually with orange or yellow marks, and they're often mistaken for pests, when in fact they eat aphids in large numbers.

Ladybirds wake on warm days in March and April and lay their eggs near aphid colonies, so tolerating a few greenfly early on means the larvae have food. Bronze fennel helps too. Sow or plant it in spring in sun and free-draining soil, and it'll flower in mid to late summer. Leave the stems standing over winter, when adult ladybirds shelter in hollow stems and leaf litter, and cut them back in early spring. Skip insecticides, which kill ladybirds as well.

Here, red ladybirds climb the stems of bronze fennel towards its yellow flower umbels. The dark bronze foliage makes the red of the beetles stand out clearly. It's the sort of small scene that's easy to walk past, chosen because it shows a garden looking after itself, with one plant drawing in the insects that keep aphids in check.