[sunshineband]

They can't usually find their way back out again  - devious but daft 

[Brassica Blaz]

I netted all my cabbages carefully from the off and I still found two types of caterpilars on them  .... mystery 

i had the same problem last year.ive double netted this year.

[JohnB47]

Last year we watched as a cabbage white butterfly twisted her wings into a small curved fold to squeeze her way through the netting covering a neighbours brassicas. The thing is, there were other butterflies in there already that couldn't get out!