BeneficialCabbage aphid
Hoverflies for cabbage aphid
Syrphidae · wild predator (larvae)
Against cabbage aphid
In UMass trials in 2018 and 2019, alyssum, dill, cilantro and Ammi majus attracted the most, and most diverse, hoverflies of the flowers tested. Alyssum is a brassica and drew flea beetles too. UMass names hoverfly larvae, lady beetles and the parasitoid Diaeretiella rapae as its natural enemies, but warns they may not prevent the high densities that build in cool autumn weather.
RateWild — plant alyssum, dill, cilantro or Ammi majus near the brassicas
TimingFrom the first colonies in early summer; most needed on autumn crops
Before you act
The adults are the striped, hovering flies on open flowers; the larvae are legless, slug-like maggots that eat aphids inside the colony. How to recognise it, what it is confused with and how to keep it around are on the full Hoverflies profile.
Other controls for cabbage aphid
- LadybugsWild predator · Nothing to release in the open garden — conserve the ones already there
- Aphidoletes aphidimyzaPredatory midge · 1–10 /m² per release, weekly
- Chrysoperla carneaGreen lacewing larvae · 2–20 /m² per release, weekly
- Cabbage aphid parasitoidWild parasitoid wasp · Wild — grow Ammi majus and other flowers near the brassicas