To avoid the hassle of trying to constantly pick eggs and caterpillars off the brassicas this year I bought a lot of cosyfleece and covered as much as I could. Unfortunately in some instances I may have put the fleece on too late, so caterpillars still developed underneath. So with the cabbages I took the fleece off about 3 weeks after putting it on and there has been no further caterpillar damage - only slugs!
The other problems are that, even though I bought widest (78 ins), any tall-growing brassicas soon bulge out, and even when they don't the butterflies seem to find a way in. It's beginning to look like an expensive mistake!
What I have also noticed this year is that there have been loads of small whites but, judging from the caterpillars and eggs laid, very few large whites. And there are almost no wasps here again - probably even fewer than last year - though I know of others in Carmarthenshire who say they have all mine and more.
