Bitter cucumbers

Have just picked our first of the season , yuk!!     Am I right in thinking that it may be caused by irregular watering?

Grew them last year with no problems.

Sometimes, if they are an all-female variety and they get stressed they do produce some male flowers and they get pollinated. Most packets will tell you if you need to remove the male flowers.

If you grow an all-female and an ordinary variety side by side the same thing happens.

There be my problem I think. We are desperately short of rain, and with these temperatures......

I used carmen this year and I have all female and they are great. Try them next year!

Picked another cucumber today , bit on the portly side and not your typical cucumber shape.  Bitter to taste so tried Bohobumble's  tip , an improvement but not to the extent that I would chomp away merrily.  I think the variety was Telegraph, Mrs Tenhens got the seeds.  Last years were meant to be smooth skinned but they were on the prickly side and we suspect the seeds got mixed up somewhere along the line.

Does anyone know why or how the rubbing of the end works?