I agree about making sure plants aren't touching windows.
During winter, the days are shorter, the sun's rays are weaker, so plants need more light than they during the heat and longer days of summer. I would try to get them as near windows as possible, without actually touching the glass or sitting on a sill. A table or other surface that can be very close to windows, but an inch or two away, will allow the cold air from the window to fall to the floor and not affect plants. Any plants sitting on the floor would likely benefit quite a bit from getting up onto some kind of table or stand if possible. Windows facing east, west, and south are the ones where sun shines directly in for a significant time (unless a tree or something like a porch roof blocks the light.)
Doubtful bulbs in a ceiling fixture would be enough to keep plants looking great, but probably enough to stay alive. Unless on a timer, leaving those on all the time could freak plants out, (they need to rest at night too,) and be unnecessarily expensive if left on only for the plants.
Putting plastic over the windows would help keep the cold out/heat in. Other weather proofing like caulk, weather stripping around doors, is usually worth doing, saving more than they cost. If there are rooms with no plumbing or plants, maybe you could close the doors and shut the registers in those rooms?
Our house doesn't have a central system, no ducts, so we heat per room, as needed, and it sometimes gets down to about 50. (Putting on more clothes is free.) IDK anything about AV's either, but have the other plants and they don't mind a bit.
A central heat system usually removes most of the moisture from the air, and plants use less moisture when it's not hot, so the less the heat runs, the longer it will take plants to use the moisture in their pots, causing plants to need watering less frequently. Just make sure there's no water in any drip trays afterward. During summer, I water plants till soaking, dripping wet. During winter, that can do more harm than good for some plants, causing their roots to rot. I do give some plants small sips when very dry during those few cold months. Don't try to keep them moist constantly, drying out is fine, as long as there's no significant wilting.
The holiday cacti should be forming buds soon, if not already. Hope you don't miss the show!
There may be other concerns, like plumbing, when letting a house get much cooler than normal, the possibility of pipes freezing. If not used occasionally, drains and toilets can have various issues. Going a little off the topic of plants with that, but well worth your consideration if you haven't already given those things some thought.
Also, the watering info is very useful!!!
Sky
). Do not, I repeat, do not allow any of your plants' leaves to touch the window panes. The panes will be the same temperature as the outside temperature is. I cannot tell you how many orchids (basically dead) have been brought to me that were growing on a window seal or close to a window and the leaves touched the window. Those orchids froze! Unless you have south-facing windows (best for fall/winter growing) and lots of indirect light comes through the windows, you need to consider supplemental lighting. Also, reduce your watering frequency by half (on average). There is no need to fertilize from October through February. In my opinion there will not be enough light/warmth for those plants to utilize fertilizer.
