[willndearne]

In a reply to a query (on another site) on caterpillars and Brassica I thought some of you might find my reply useful;

I have found total success with Bacillus thuringiensis! This was the bacterium that made Louis Pasteur famous before he invented Pasteurisation. These blighters almost destroyed the Lyon silk industry until he discovered them killing the silkworm caterpillars and instituted simple hygeine to the rearing cages. I bought the spores in a carrier powder some years ago under the trade names on BioBT and Bactospeine w p. Both are a wettable powder of which I mix a small quantity in a bit of water in my sprayer and then top it up. The spray is effective against many caterpillar pests on Brassicae, Strawberries, Raspberries, Tomatoes, Cucumbers, Peppers and ornamentals (so the blurb says; I've only ever used it on Brassicae). The caterpillars have to ingest contaminated leaves after which they become moribund and die. Unlike chemical pesticides there is no residue in the plants and washing will remove any remaining bacteria (which don't affect humans anyway). Biobt can be bought from http://www.homeleighonline.co.uk/bio-bt-caterpillar-killer-8-sachet-pack... but I can't find an online supplier for bactospeine
Hope your brassicae survive and thrive; it's been a weird season. My second sowings are way ahead of the first because of the cold spring

Will

[Salmo]

That link no longer works but this one should
http://www.homeleighonline.co.uk/gardening/garden-care/pest-control/bio-bt-caterpillar-killer-8-sachet-pack.html

Good to hear from someone with experience of this. Do you need specific conditions for sucess.