Don't know why your hardies haven't flowered but the second question is yes, keep them dry whilst dormant. Try to keep the compost from freezing though if the greenhouse isn't at all heated. You could try wrapping the pot in bubblewrap, and perhaps covering loosely with fleece if there's a hard frost expected. If we should have a hard winter it would be safer in an unheated room in the house, but still kept dry. It will lose all its leaves. Then in about March you can water it gently , cut back most of the dead stems and treat the remaining ones with a fine water spray several times to encourage new buds to break.If you prefer you could spray first and prune afterwards when you can see where the new buds are forming.

Thanks very much for your detailed answer. I'll definitely do as you suggest.

The most likely explanation for the no show of flowers so far is the heat - fuchsias aren't keen on that, and being very dry probably means the bushes have decided its not appropriate to flower right now. Many plants in flower, subjected to drought, will first drop the flowers, and then the leaves if things don't improve as part of their survival strategy.

Thanks. I hope it's not too late for them to flower now.

Don't give up. Some of mine haven't fully flowered yet either but there are buds showing most of them. Its a very late season for them.

Thanks

I overwintered 2 of the same fuchsia and the same size in my shed last winter and one died but the survivor is doing really well. No idea why one died as they were same in every way. Taking cuttings off the survivor!