Last winter even with a little heat I lost all of my fuchsias in greenhouse.

What I have done in the past is take fuchsias out of their pots and prune back and wrap in newspaper put in a box and then put them in loft till Spring.

Another method I have heard works if you have deep trench lay your fuchsias and cover with straw.

i put my plants in their pots into the compost/soil in the ground, then place some rigid plastic sheeting over them like a tent. i find that the compost seems to keep slightly moist most of the winter, and also if the plant does appear dead it will send up shoots from the roots in the spring if i'm patient