Cucumber not fruiting

[Penellype]

From what you say I would think it is lack of pollination. Marketmore is definitely an open pollinated variety. Having said that, my cucumbers are very stop-start this year, with a lot of the fruit shrivelling up and going yellow, and mine are all female varieties.

[Plot70]

It has been a real pain getting the flowers to set.
The amount of male flowers has been stupid on a grand scale.
Then finally they have started setting.
Last year an outdoor cucumber formed in the leaf litter and got missed until the first frost. The seeds grew and I have had a small fruit off one of the resulting plants.

[goosander]

Never had much bother with cucumbers until this season. Hopeless with very few fruits. Most have just given up. Was wondering if the very hot days and cold nights are the problem.
Bob.