Allotments 4 All

Not important at this time of year, but why?
Only on one plant, at the top.

Managing to keep blight at bay by removing all affected leaves. = Tim

Like your problems earlier in the year I would guess your night time regimens are causing some stresses, Tim. Without a circulating fan or a heater you will be getting dead air spaces in the greenhouse that will result in this localised, apparently random, tissue damage.

Right, John - I'll put a fan in! = Tim

Wanted to convince my wife that it was all worth while.
Looked up 2 quotes which I put together here as a matter of general interest.

Thanks again, John. = Tim