- Regularly check the plants from mid-April onwards for sawfly larvae and pick them off by hand
- A biological control (pathogenic nematode), sold as Nemasys Grow Your Own, can be watered onto infested plants. The nematodes enter the bodies of the sawfly larvae and infect them with a bacterial disease. This nematode is available from some garden centres or via mail order
- Spray when young larvae are seen, with an insecticide approved for use on the appropriate food plant. Make sure that the manufacturer's instructions are followed.
- Suitable insecticides are thiacloprid (e.g. Provado Ultimate Bug Killer), lambda-cyhalothrin (e.g. Westland Resolva Bug Killer), deltamethrin (e.g. Bayer Provado Ultimate Fruit & Vegetable Bug Killer) or an organic pesticide such as pyrethrum (e.g. Py Spray Garden Insect Killer or Bug Clear Gun for Fruit & Veg)
- Plants in flower should not be sprayed due to the danger to pollinating insects
Pesticides for gardeners (Adobe Acrobat pdf document outlining pesticides available to gardeners)
Biological control suppliers (Abode Acrobat pdf)