Are there any strawbs specifically bred for growing in poly-tunnels? At the moment I've got Cambridge favourite, which taste very good, however, the yield under cover isn't as prolific as the ones I grow outdoors.
Could it be that being undercover they are not getting as many passing insects to pollinate them. I have Elsanta in the garden and they are prolific I've had about 3.5 kilos so far from 18 plants this year.