I've grown gardenias in the DC area for several years. II started with a few from nurseries in the early 2000s. After some mistakes with overwatering in summer and freezing in winter I finally got the hang of it and have only lost two plants since 2008. I have four which are thriving, one is three feet by two feet by two feet in a large windowbox. The key here unless you have a VERY sunny window in winter is to overwinter them in very cool conditions. I keep mine in my unheated garage. They will tolerate long periods of darkness when cold (30-45F) and if it's warmer than that they can go outside. About a quarter of the winter days here are warm enough to leave them out. Temperatures below 25F damage the flower buds and newer growth. Conversely in summer I give them 4-6 hours of sun, preferably morning sun. In spring and fall they get full sun. WIth this regimen, I get small flower buds in November. THese overwinter and start growing in April. Around Memorial day I get flowers and they bloom until about July 4. After that they start dropping buds and generally don't do as well in midummer heat. (low 90s days, mid 70s nights). From mid July to sometime in late August they don't seem to make buds and just grow leaves but after that they make buds again. Late August buds start blooming in early October and I just got my first three today. Cool weather from mid November on seems to slow the big buds enough that they just die on the plant, very slowly. Small buds do okay. I never let them dry out but don't keep the soil sodden either. Their pot will keep them moist for two sunny dry days so I try to keep it on the dry side when I am not on vacation or otherwise gone and water it to half capacity. Overwatering in summer is lethal. I use pro-mix for potting soil although I am not happy with it for long term (years) use. Every few years I cut them back hard to main branches. There is a second type I have found in my neighbor's yard. THis has 5" typically fragrant flowers in June (fall flowering is not as good as the florist types) and is fully hardy here in Zone 7. It is at least 20 years old, has 6" trunks and is obviously thriving. It gets full midday sun. I just got cuttings (with permission) this summer; they've rooted and I'll see how they do. He does not know the origin of the plant but the local Home Depot sells a very similar one which is said to be hardy. I've never tried it. The point here is that like the Spokane WA poster earlier, gardenias will tolerate a lot of chilling and light freezes. They do not like the combination of warm, dry, stagnant and dark that they get in a typical house in winter.

This is sort of unrelated, but just an FYI....the Target stores here have Aimee gardenias for under $7. Might not be available in different regions, but I feel worth looking there to see if your local Target has them. And there is a lot of growth for a 1 gallon pot, very lush compared to gardenias from other garden centers. For $7, I think its really worth the buy, even if it lives for one month or to use it as a indoor guinea pig. LOL.

I have never grown this indoors, and these article has some tips, if you haven't seen it already. https://hort.purdue.edu/ext/gardeniachallenge.html I would probably not attempt it indoors unless I had a sunroom or a large South facing window. They like humidity too. Have you thought about putting it outside on a patio in summertime? My mother has these around her house (of course she's in the Deep South with 1000% humidity in August) and they do very well as outdoor shrubs. Will let the experts weigh in.

Hello all, A few years ago my neighbor moved out and left a small plant that I later realized was a gardenia by the trash. I'm not an experienced gardener but I felt bad for it so I brought it in. It has flourished (I'm not sure how as I don't know or do much with it) and is now so large that I have to lie in wait to get men to come move it outdoors for the summer and back in (I am in New York City). I noticed about 3 weeks ago that it had some small white flies on it. I sprayed it with Safer brand insecticide before I noticed that the label says not to use on gardenias, but the flies were gone and all seemed fine. I had it moved indoors--and now suddenly the whiteflies are all over it, and many of the newer leaves look finely dimpled. Can I try managing the population with sticky traps and wiping leaves down? I've read a bit online and it looks as though I need to spray it repeatedly, but I don't see how I can do that with a plant this size indoors, and it seems too cold to have it outside any longer. I'm not sure if I should be just minimizing their damage, trying to kill them all indoors maybe by cutting the plant size back some so I can, or putting it back outside so I can spray it more liberally. Can anyone tell me 1. what to use (soap, oil, neem?) 2. whether I could do that indoors 3. how much cold it can tolerate outdoors? Maybe I could put it back outside and spray it this week and next before it got too cold, then bring it back in. This plant has given me so much joy and I'm afraid I"m going to lose it. Thanks so much for any insight. Photo attached.