What's eating my arugula / rocket?

Arugula (rocket) is a brassica, so flea beetles are its number-one pest — the tiny jumping beetles riddle leaves with holes overnight. Slugs attack seedlings, and cabbage white caterpillars graze leaves in summer. Because it grows fast, sowing successionally under row cover often sidesteps the worst damage rather than requiring chemical intervention.

Dozens of tiny round shot-holes across leaves, reducing marketability and photosynthesis; worst in warm, dry spells. Grow under insect-proof mesh at all times; sow in late summer for a less-affected autumn crop; apply kaolin clay.

Irregular ragged holes in seedlings and young leaves; slime trails on foliage and soil. Apply iron phosphate bait; water in the morning so soil surface dries by evening; hand-pick at dusk.

Larger holes than flea beetles, with frass present; mainly affect summer-sown crops when butterflies are active. Inspect undersides of leaves for egg clusters; hand-pick larvae; protect with fine-mesh covers to exclude butterflies.