Whatever it is, it started to sweep through the allotments on Wednesday.
Three years running but this is the worst year so far. Location SE Cornwall,
5 miles inland, 500' amsl, East facing, 1 in 10 slope.

All allots have removed their potato haulms. I have 6 rows with : Foremost,
Premier, Estima, Marfona and 2 x Accent. I've dug up the Foremost row and
got about 12 egg sized spuds from 12 plants !! My neighbour who planted 3
rows of King Edward got zero returns. He's hoping for better results with 6
rows of Casablanca. He's removed haulms on these also.

Not sure whether it's blight or blackleg. None of my tubers showed the
damage seen on these images and only SOME of the stems have gone dark :-

http://preview.tinyurl.com/ztjc6la (blight)

http://preview.tinyurl.com/jy9nezv (blackleg)

The allotment size is about 50 metres by 6 metres and the traditional
planting method is to lay seed pots ACROSS the slope, then banked up into
ridges as the leaf pokes thru'. Perhaps it'll improve the drainage if the
rows were laid DOWN the slope?

Looks like damp weather due to adj Jet-streams are going to be a feature of
our climate but I guess the obvious answer is to have a get-together with
the other allotments and agree to a ban on spuds - but for how many years?