Mine took absolutely ages but they are now producing and we are eating them.

It may be the problem I have had this year. Firstly there were no flowers of the different sexes open at the same time, now that some flowers of both sexes are opening together, there are few pollinating insects around i have managed to hand pollinate a couple, but I wait to see if it was enough.

Mine were very slow starting - and when they did, the gastropods got the lot.