Great info Leo. Thanks for sharing. They said dont go below 5oC with these. Scotland should be good for them but a few guys have killed all of theirs off over the years at the club over watering in winter.
Can they afford to dry out a bit or would you suggest mildly moist over winter in a shaded area of the house?
Nobody in the Scottish Bonsai Association has had any success with these as far as gathered at the show
5 C as a minimum should be fine. I did visit Scotland once, and was struck how long your days were in June. Hence, your daylight is very short in winter. I run my Fuchsia under lights, with an 18 hour daylength, all winter long. This long day length helps with compensating for lower light intensities under lights. and helps keeping the plants growing. I would get blooms under lights. Most Fuchsia species occur from Colombia south thru Peru and into Chile, in the Andes mountains, this whole region is close enough to the equator that it is unlikely the Fuchsia are day length sensitive. Meaning, you can give them long day length year round and they will just keep growing year round. They do not have or need a marked dormancy. IF kept warm enough, above 5 C, and bright enough, they will keep growing all year round. It is possible that in Scotland, the winter day length is too short to keep Fuchsia happy, which means wintering in a greenhouse or on a windowsill without supplemental light might be a problem. But I am just guessing.
I have always used a potting media that I would use for azalea or maples or hornbeam. I usually use a media that is near 50% composted bark. I have also used Kanuma, and Akadama with good results. The few times I used a potting media appropriate for Pines, an all mineral mix dominated by pumice, the Fuschia did poorly.
I have also used a potted plant, houseplant media, based on peat moss, this actually worked well too for sizing up small plants to develop trunks. This was for plastic pots, nursery containers, not for fine bonsai pots.
So I believe they need a somewhat ''organic'' mix. I never dry them out entirely. Lightly moist is as dry as they get.