BiscuitBoy Jr, hard to say, but my guess would probably be something like Phytophthora infestans, which unlike most Phyto's is active in cool weather. A cool-weather root-rot fungus of some kind would be my best guess.

Conifers per se are unlikely to have harmed the Fuchsias, but they might have had the disease themselves.

How is drainage?

Fuchsias are not extremely susceptible to root rots, but highly-bred and young plants are more susceptible than species and established plants. If you're having trouble overwintering plants, consider switching to more reliable and vigorous hybrids and species. Hard to beat Fuchsia magellanica var molinae for vigor (I've had them exceed two meters).

I don't know what to say about the root other than sometimes sickly shoots don't quite make it. Keep it from getting frosted and give it a little TLC for a while, until it starts growing away in earnest.

All my fuchsias are now in the plastic greenhouse, (best I have) but one of the varieties there was classed as 'super hardy', Army Nurse. P.S. How can I get rid of Phytophthora infestans? And what do you mean by highly-bred plants?