The Cabbage Whites.
Oh, while writing this, I came upon this!
http://www.fcps.edu/StratfordLandingES/Ecology/mpages/cabbage_white.htm
Poor prospect??
But the way they have fooled me this year is that the 'cats' are only 1cm long with no stripe. And, with my eyesight, I have missed an awful lot!!
Answer to your question - around mid-September? ;)
I so enjoy the sight of them dancing over the plot (deeply frustrated no doubt) thanks to MESH ;D
http://www.allotments4all.co.uk/joomla/component/option,com_smf/Itemid,72/topic,22704.0
(chortle)
And when do flea beetles stop their nibbling activities?
My allotment neighbour has built a beautiful cage over her brassicas, I noted yesterday that it had half a dozen cabbage whites flapping about inside.
I cage all brassicas all year against sky rats & the dreaded S/L whites. You see them inside the net, you whack them with a stick & the b***ers pop out! I reckon they are mice on a different plain.
Are well, I'll be up there tomorrow inspecting every leaf/sgwigging the eggs/caterpillars - they shall not have them!!!!!!!!!1