- Sow sparsely to avoid thinning the seedlings. Female carrot flies searching for egg-laying opportunities are attracted by the smell released when surplus plants are removed
- Late sown carrots (after mid-May) avoid the first generation of this pest; similarly carrots harvested before late August avoid the second generation
- Protect vulnerable crops by surrounding them with 60cm (2ft) high barriers made of clear polythene to exclude the low-flying female flies, or cover the plants with insect-proof netting, such as Enviromesh. It is essential to practise crop rotation with these methods, otherwise adult carrot flies may emerge within the protected crop from overwintered pupae in the soil
- Choose carrot cultivars that are less susceptible to carrot fly, such as 'Fly Away', 'Maestro', 'Resistafly' and 'Sytan'. These cultivars are less susceptible to carrot fly, rather than being fully resistant
- A mixture of pathogenic nematodes, sold as 'Nemasys Grow Your Own', can be watered into the soil to control the young larvae. This is available by mail order from biological control suppliers
- One company, Just Green Ltd, Unit 14, Springfield Road, Burnham on Crouch, Essex CM0 8UA, 01621 785088, supplies a predatory beetle Atheta coriaria for carrot root fly control.
Lambda-cyhalothrin (Westland Resolva Bug Killer) can be sprayed against the adult stage of this pest. There are no soil-applied pesticides available for garden use against carrot fly larvae.
Pesticides for gardeners (Adobe Acrobat pdf document outlining pesticides available to gardeners)
Biological control suppliers (Adobe Acrobat pdf document listing biological control and suppliers)