it's likely that their growing conditions are not indoors so, container or no, they produce plants for the market outside and in quite different conditions than what you are trying to do.
probably nothing more than regular water and fertilizer, perfect lighting and warmth. i've seen zenobia pulverulenta and franklinia altamaha growing on the hot, black tarps in baking sun at a local nursery and, as soon as i take them home and plant them in perfectly natural growing conditions, they croak!
you may have to resign yourself to treating them as annuals as they are not the best candidates for cold-climate indoor culture, esp. based on what i read on this forum.
they are quite common in zone 8 but i don't know if i would try to overwinter them inside if i had to. if it's any consolation, most of the highly fragrant lilacs don't prosper here in our heat but many of us wish they were as easy as the gardenias. ;-)

You know,,,you're right!

If I can make a few last through the winter, then that is something to be greatful for.
I suppose if I had a year round greenhouse with all the perfect enviromental factors needed for them, I would consider them perenials.

Since I do not, then I will have to look at them as annuals, and if my miracle, a perenial when they make it through our harsh winters.

You shouild smell all my huge awsome lilacs right now. Thanks for your insight!

Mike..:-)

P.S. I guess barely any nursery owners frequent here.......They should to see what we are all saying, and share their sucess, unless they do come here, and decide to add nothing to this forum.....

Vinegar...Yup that is what it is....;-)

All my gardenias pretty much croak by late winter too. I am going to buy a heating mat this year, and I am also going to put a bunch of lights on the thing too, if I had had more light and heat I know my gardenia would have survived. And no I'm not in denial, ha ha! It had one big fat bud that was near the light bulb. If it hadn't gotten throw off the deck, it may have even BLOOMED! Ya, ha ha ha!!!

meyermike, i'm glad someone else thought to ask the nursery people about this. there must be something we're missing, since the plants i buy are always dark green and full of big fat flowerbuds. i brought one home two days ago and put it in a bigger pot and the buds dropped off 36 hours later. grrrrr! maybe i shouldn't have moved it into the bigger pot?

and jeff al, i feel your pain too. how can mine be so fussy here, and yet last summer i saw one going crazy in the parking lot of a green mill restaurant?! i know the cooks aren't taking time out from flipping pizzas to give it miracid.

I am not a nursery guy and I do not have any magical answers for you but some trial and error learning that took me a few years (I would say I killed a few hundred over time -- that I am willing to admit to). I am a simple country gardener and I grow them outside in Zone 6, so I have no tips for container growers. I also do not grow the hothouse variety because of my zone, those are the ones you get around Easter.

Yes I know they say it's 'iffie' here as prennial but someone should have told me that many years and plants ago.

My rule is the first year is a wash do not expect anything but stimulate the root growth. Remember when planting it is a wood plant so treat it like a bush your transplanting... this was my hardest lessen. You have to sacrifice the first year you plant it of great flowers if you want it to stay alive, acclumate and grow its roots. At least in my zone.

I plant mine where they get sun a good portion of the day but not all day and I have learned to keep them near the light post or garden lights. We have an outside air conditioner/ heater which blows hot air when running... They really love it near there.

I cut them back when I cut my roses back in the late fall using the same rule... anything smaller than the width of a pencil.

The other things I do: I plant hostas at their base to suck up too much water, we have clay soil so I plant them on a slight mound with rocks under for drainage and mine seem to really like coffee and flat soda in the summer. Oh I also keep them in the same bed I have my lenten roses, I find that if the lentens can come up in the winter then that part of the soil is not too frozen.

My oldest one is around 8 or 10 years old but it has had many offspring. Hope this helps someone.

Now if I could just grow a peonie..... :-(