[Johnoneill2000]

My tomato plants in my Polytunnel which had been doing great have just started to turn spotty and black and is happening really fast as I cut back yesterday and today same problem I also notice that some tomatoes turning black aswell , is there anything I can do to stop it ?

[michael brenock]

sounds like potato blight, picture would help. if the blackening is firm and flesh is also black then it is likely to be blight. Though it was not a bad blight year a tunnel would provide an ideal site for blight if it was not ventilated, Small black sooty spots on skin are harmless the result of aphids on upper leaves/
michael brenock