potato blight

I haven't tried it, but i don't believe it would be effective - spores that cause fungal diseases are very small - 30 - 40 microns - environmesh is about 150 microns, so the "holes" would allow the spores through. Additionally, they can live in the soil for 3 years, and can also be washed onto your plot form neighbouring plots if there is heavy rain. The humid conditions would also make blight more likely. Your best bet is to either only grow earlies so they are harvested before late blight hits, or to spray at weekly intervals from June onwards. There are some blight resistant varieties which people on here have mixed opinions about. I grew Sarpo Mira which didn't succomb to blight, but found that it didn't give me many tubers, although the ones that grew were of a good size.
HTH
JMW

Many thanks for your replies.I think I will have a go at spraying next year.The blight seemed to come here early this year up here in N-E Scotland.I  managed to cut down the foliage early as soon as it went black so managed to save the tubors but they were a bit on the small side.