What problems and pests affect arugula (rocket)?

Arugula is a brassica, so the main pests are flea beetles that pepper the leaves with tiny holes, plus aphids and caterpillars, and downy mildew in cool wet conditions. Because it is eaten raw as a quick baby-leaf crop, control should be soft: insect netting over beds, clean fast growing, neem-based options and only labelled products with safe pre harvest intervals. Flea beetle damage is mostly cosmetic but buyers reject holed leaf, so netting is often the simplest fix. Bolting in heat is the other big quality loss, handled by timing and quick harvest. Confirm any product use with your KVK.