[Princess1]

I have 2 pepper plants, both producing flowers but the flowers simply fall off without producing peppers.? The plants themselves are strong.

1 is in the greenhouse and the other outside. Any ideas?

thanks
Princess

[sunshineband]

They could be either too wet or too dry at the roots.

Try this first

[JayG]

Have they already set any peppers, as they will only set as many as they "think" they can successfully mature in the growing conditions they find themselves in?

We don't know where you live as you haven't put your location in your personal profile, but peppers can be a bit "marginal" outdoors in a typical English summer; the indoor plant might benefit from a bit of a shake from time to time to distribute the pollen in the flowers to help pollination.