[gardener247]

i grew potatoes and they got blight the soil was all weeds and i am not going to turn it till spring.. i plan to set up my polytunnel in this area... the winter was cold to -10 so will the blight overwinter on th grass... will this be safe

[Aunt Sally]

Your ground will be fine. 

Late blight survives mainly on infected potato tubers in dumps, or in volunteers (the potatoes that get left in the ground when you dig up the crop) or in seed potatoes.  In the spring some of the infected tubers produce infected shoots.  The infection is then spread by wind and rain and becomes a problem when the humidity and temperature is high.

[gardener247]

i left the spuds in the ground cause they were mushy and disgusting but the winter was very very cold will it be okay

[goodegg]

i think the blight will still be there because you left the spuds in the ground when they shoot they will start the blight of again you should try to dig them up as they shoot and burn them dont compost them.