Cabbage root fly: how to spot, prevent and treat it pest
How do you spot cabbage root fly?
Transplanted brassicas grow poorly, droop and die, most often in a first wave in late spring. White larvae without legs or head bore into the root collar and the roots.
On particular plants
black radish: The larvae eat out exactly the edible part of the root.
radish: The larvae eat out exactly the edible part of the root.
How do you prevent cabbage root fly?
Keep to a rotation, because the fly hatches from pupae that overwinter in the soil under the previous brassica. Protect transplanted plants at planting, not at the first sign, because by then the larva is already in the root.
What works against cabbage root fly?
Lay a collar of felt or cardboard around the root collar, so that the female cannot lay her eggs against the stem. A cover of fine mesh that stays on the bed through the whole season is more reliable.
Which plants get cabbage root fly? 9
Vegetables 9
Sources: EPPO Global Database, Royal Horticultural Society
Checked on 17 August 2026.