What plants do you want to overwinter? Depends on what plants for the best advise to overwinter. Generally, tropical marginals can be brought indoors and left inside their pots submerged inside a a second waterproof container (a bucket). Situate them in the sunniest window you can find and keep the bucket filled with fresh water and occasionally add weak liquid fertilizer. You can prune or divide if you want to trim them up for winter. Or bring in a few nice pieces and discard the rest. Large planters filled with water can be daunting. Some plants lend themselves to planting in soil like elephant ears and placed in sunny windowsills. Water and fertilize when needed. Plants like water hyacinth and water lettuce, best to throw those out IMO and start with a couple of new plants each year as they don't overwinter well inside and they are cheap to replace. Tropical water lily you can pull the whole pot and put in a plastic bag and put in a cold, but frost free location (like a basement). The idea is not to actively grow them all winter but to keep them alive, semi-dormant. Some folks keep them actively growing in an aquarium. Some had said they have no luck at all with overwintering tropical waterlilies and replace them. Unless the plant is rare or expensive you may find it less hassle to just buy new every season. Sometimes if a plant is on the edge of it's zone you can leave it outside provided it is well protected. Like a zone 8 plant in zone 7. But, a zone 11 plant will bite the dust in all but the most tropical locations, without going to extraordinary measures (heating coils and greenhouses).

BTDT with the indoor 'jungle'! Was fun but too much work now. If I had a sunroom I might do it again as I could then keep my 'plant-eating-cat' away from them. Lilyfinch, your citrus trees should do fine. Years ago I grew some from seed and put them outdoors in the summer, indoors in the winter. I used to overwinter various plants. Tried to keep Rosemary over several winters but with limited success so I seeded plants and bot others. Thymes, sage, parsley, and oregano are others I used to bring in and keep on my kitchen windowsill - last winter they survived outdoors anyhow. I used to bring in chives to use also altho they do well outdoors. I never found the herbs lasted all that well indoors with our long winters so no longer do that. They were usually good for 2-3 months then compost. When I grew coleus they always did well when brought indoors altho need to be kept well trimmed - of course I always potted up the 'trimmings' so would have lots of plants by spring! When I lived in Europe my landlady would trim back her geraniums, plant the cuttings, and keep them all in an unheated attic. The only plant I'm attempting to overwinter this year is my Lavender Dentata 'Serenity' which is a zone 8 plant I bot as an annual. However, it's been such a nice plant that after I took cuttings for potpourri I decided to move it indoors. It's growing well and is even budding altho on short stems. I have it in a south window and am not watering much so I'm hoping it makes it thru the winter. It's a good one to have in my house as I like to touch it for the scent and the 'plant-eating-cat' doesn't like it.

the survival of both sets of plants depend on the fact that the roots will freeze IF the soil temperature drops below 28F... SO... keep the soil damp (every time the ground thaws then water) & mulch the plants but look for mice moving in....

Thank you for the holiday wishes and same to you, GarnerGarden! I think that the peppermint would have been happier, outside. The indoor air is probably too dry for it and my peppermint, and several other mints, do fine outdoors through the winter. Obviously, it's in a pot so that puts the roots more at risk to the cold. Perhaps, you could sink it, pot and all, in a hole outdoors. The rosemary needs winter protection. Some of the lavender does but I don't really know. Don't know about the proper care of the lemon, either ... Parsley is a biennial. I sow parsley seed every year for fresh plants. I think it will, more or less, be okay on its own. When I was a kid, we had a little parsley patch that always had some nice leaves. I think only some of the plants were flowering each year and that there were several so that they were always at different stages of development. About the rosemary, it would probably need to go dormant, or nearly so. I would lose as many as half my rosemary plants trying to keep them in a too warm basement over winter. I finally began keeping them on the floor of an unheated greenhouse and covering the plants when they would be going much below freezing. hope some of this helps a little. Steve