Fighting the carrot fly

The carrot fly (Psila rosae) is an insect that belongs to the Diptera family. It is one of the most problematic pests of carrots and other crops such as parsnips, celery, parsley, etc. Its larva feeds on the roots of these species and renders a large part of the harvest unfit for consumption! What is the lifestyle of the carrot fly? The adult is a small fly, 4 to 5 mm long. The abdomen and thorax are black and the legs yellow. On the brown head, you can see large white cheeks. In winter, it hibernates as a pupa and then appears from late April-early May until July. Carrot flies fly in tall vegetation and feed on pollen and nectar. They are able to locate their host plants by their smell and generally fly very close to the foliage. Females lay about fifty eggs in the soil near growing plants. About ten days later, elongated, white larvae measuring 6-7 mm emerge. They feed by digging brown tunnels in the roots. Brown spots are also present on the roots. They are often invaded by rot and their taste becomes bitter. The larvae transform into pupae which will give rise to a second generation of adult insects between July and November. This generation, very harmful, causes damage until October-November! Two to three generations are possible between late spring and autumn. How to control the carrot fly? Control the presence of these pests: You can identify the time of the flies' flight between April and October by placing a yellow bowl in the garden containing water and dish soap. Sow after the first flight of the flies to avoid any invasion. Sow in May in the south of France or in June in the north. Do the same thing in the fall and sow after August. Do not sow too densely to avoid thinning out later. Female flies looking to lay their eggs are attracted by the smell of the seedlings when they are removed. Try several varieties. Some attract carrot flies more than others. Highly attractive varieties can be used as trap plants. Alternate rows of carrots with plants with fragrant foliage such as marigolds, onions, leeks, dill, coriander, etc. Spread coffee grounds or strong-smelling plants such as wormwood, ferns, lavender, tansy, etc. at sowing time or during their development period. Place orange sticky traps in the carrot plot. Lay down an insect net.