Well, they really are NOT indoor plants. If you're in a zone 7 (or even 6b), you could grow them outside (which they would REALLY prefer). Containerized, I would keep them as cool as possible during the winter and put the plant out for the growing season. I don't have a Little Gem but do have (in the ground) Majestic Beauty, Victoria, Edith Bogue, and Greenback (in addition to a few deciduous one)--I love Magnolias! But getting back to your questions, Magnolias require acid soil (lower pH)--you can purchase fertilizer for acid-loving plants. Don't feed at the outdoor rates if you're only growing indoors. Obviously, full sun if you have it. Good luck!

Thanks so much for the replies. The reason for the dwarf is space. I saw Teddy Bear recently and really liked the dark color of the leaves. It was standing next to Little Gem, and there wasn't much difference, though TB might have been a bit darker. I initially liked Alta because of its upright form, which would work well in my space, but from what I understand, TB and LG might also be upright? I wish I could order some of the more interesting varieties, but I want as large a size as I can afford right now, and I'm afraid shipping would be prohibitive on that. I just talked to someone today who said LG is hardy in my area. So if TB and LG are also upright like Alta, then I have 3 choices which work in terms of size and form. I just don't know how to decide among them. Is one faster growing than the others, maybe? Thanks again.

If you can provide it with the proper conditions and possibly some microclimate protection, my guess is that it will do just fine. Without a little microclimate protection chances are still decent. 'Little Gem' is hardy to around zone 6a (some list it hardy even through zone 5). Niagara Falls has been around 6a in the past decade or so.

I think sometimes people plant things based on what they see and don't see in other peoples' yards. Over ten years ago I planted a Magnolia graniflora on the south side of my house in suburban Bergen county (central eastern part). Technically, I believe we are listed as zone 6b but I have a lot of plants from zone 7 (camelia, Acuba, etc.) This is the big-leaved variety (not any super hardy dwarf form). I am familar with only a couple others planted around here but have noticed them being sold more frequently now around here. This tree has grown beautifully. Much better than I ever expected it too. The first two winter I remember were really bad (record cold, record ice etc.). The first couple of years, I would spray it with an antidesicant in the fall. Now, that would be impossible to do even if I wanted to and it has passed through the last several winters without ANY leave damage. I have had to cut back the lower branches of a large white pine that is growing in the vicinity of the magnolia in order to give the magnolia more room. (It is reaching beyond the second story at this point.) I think the significance of microclimates is underestimated. This tree is on the south side of the house and partly protected by adjacent conifers. My only regret is not planting it further away from the house. A lesson to everyone who plants a tree; however far you want to plant that tree, PLANT IT FURTHER AWAY!!