Greenfly on potato flowers

Greenfly are the main spreaders of viruses in potatoes, the peach and potato aphid. This is why they tend to be grown in Scotland and coastal Northern Ireland where the wind tends to blow the winged form away to sea - according to Lawrence D Hills.

I've found them in the past on the sprouts when the potatoes were left chitting in a conservatory near some pot plants brought in for the winter. The greenfly in our garden seem to prefer nettles, this year at any rate which suits me.