The interesting thing this year, is that in April I planted a separate much later crop of 'Green Windsor' (which my Sister bought in Poland!) As usual, the nasty blackfly quickly set up home on my first batch of the earlier 'Express' despite having pinched the tops out. This first crop of beans (above) did not suffer however, but they were quite badly covered. The later crop of 'Green Windsor' (see foliage) was completely un touched! Not a single blackfly. I am assuming that the first crop was a 'sacrifice plant' and the blackfly just couldn't be bothered to fly over to the second crop. They are now about to crop, and they are perfick !