I would spray regularly with B.t., Madeline. It doesn't hurt people, pets, or wildlife, but does kill the caterpillars at first bite.

what is B.t Tugbrethil?

If you dont want to spray then you could try planting nasturiums as a companion plant. You can buy a fine mesh that may keep the butterflies off.

Logging in because I want to know what this B.t. is!

bet we cant get it in britain bulbaholic !

BT is a microbial insecticide which contains living spores and toxic crystals from a soil bacterium called Bacillus Thuringiensis (bt)...It only kills the caterpillars....sounds real good doesnt it?......If anyone knows where it can be bought please let us know.....or mail-order...:>)

Here in the States, it's available from VPG (ferti-lome & Hi Yield brands), Green Light, Bonide, Woodstream (Safer & Concern brands) and Lawn & Garden Co. (Monterey Brand), if any of those are available in the UK. The active ingredient is one form or another of Bacillus thuringiensis v. kurstakii, and it's available as a liquid concentrate, or as a powder suitable for dusting. I've never seen it as an RTU spray. I hope this makes it easier to find!

thanks. I have heard of the bacterium and i think it may be one for the commercial bods.