Carrot Fly, Carrot Rust Fly, Carrot Root Fly
The Carrot Fly is a pest of Carrots, Parsley, Celery, Celeriac and Parsnip. It's the larvae which are most damaging to plants. They bore into the plant taproots, eating the inner contents, and disrupting the movement of water and nutrients. Carrot Fly will deplete most of the rooting system of a plant, resulting in a substantial reduction in the top growth of the plant, which ultimately loses colour and wilts. Infested plants may also be susceptible to secondary rots. The top growth of Carrots, Parsley, Celery, Celeriac and Parsnip should be monitored between mid-spring to late autumn when Psila rosae activity is highest.
Carrot fly can damage leaves and roots, sometimes killing plants.
Adults: The adult is a tiny winged black fly which rarely flies above 60cm from the ground and lays eggs onto the soil surface. Larvae: The larvae are thin maggots, creamy-yellow with a black dot at each end of their bodies and are 7 to 9mm in length. Pupae: The pupa stage occurs in summer and overwinter. Generally, there are two generations per year.
Tiny maggots bore into roots and in the crown and petioles of Celery. The part of the plant above the ground wilts. Reddish-brown foliage in Carrots and Parsnip. Yellowing of foliage in Celery. Overall stunted growth. Crop is damaged by boring and may rot.
Asia, Europe and North America
As the Carrot fly is a low flyer, erecting a barrier around the crop will prevent it from being able to fly into the area. Using a fine horticultural crop mesh or fleece over the crop and the loose sides dug into the soil, will protect the crop from the Carrot fly. Another way to deter carrot fly is to sow thinly. This removes the necessity to thin the crop, minimising the scent released and deters carrot fly. Choose to grow a variety of carrot resistant to carrot fly. Yearly crop rotation so over-wintering pupa does not hatch to a suitable crop. Likewise, sowing seeds later in the year (from June onwards) will allow you to avoid the first generation of pests, minimising damage to the crop.
Check availability with your local garden centre.
Companion planting of strongly scented plants to detract from the smell of the carrot crop.