here are the roots picture

Can you plant this in the ground?

rosiew, no I live in an apartment so I can't :( It has to be in a pot

search the fragrant plants forum at the link below.
there are many posts from northern gardeners about growing gardenias indoors.
the fire escape location sounds like a good spot to keep it during the summer. heat doesn't bother them but you will want to make sure it doesn't dry completely out in the container.
we grow them in the ground here so i don't know much about growing them in containers and overwintering indoors.
you can make a link to this post on the fragrants forum and you won't have to retype all of your information. good luck with your efforts. they have some of the most fragant flowers of plants i have encountered.

Here is a link that might be useful: fragrant plants forum

Gardenias like sun. Keep it as much as you can getting some light. My understanding they are not a houseplant so you would want to put it outside like you are doing for those hours of sun, if you can. I would get a larger pot, a size or two larger if you can fit in your apt. Get a very lightweight pot whatever your budget can afford. There are beautiful pots that look like stone etc but are plastic or some sort of polymer. Then I would purchase some potting soil, if you can afford get the one with fertilizer and water holding pellets, the soil should be as lightweight as possible. Usually the fertilizer lasts 4 to 9 months. Read the bag. Before potting, very gently tease out the roots so they will sort of be pointing out into the new pot/soil. Keep the top of the soil at the same level as the soil is now on the plant's stems. All of this will shock the plant a bit so expect some yellow leaves and maybe some wilting. Keep it watered but draining water well. If it looks like it is about to bloom you might want to wait until after the bloom period to do all this. I hope this is helpful.

jeff_al, Thanks a lot for the link it was very helpful, yes I will post this there as well.

louisianagal, thanks for your help, yes I purchased everything including an 8 in container, it is currently in a 6 one so I think 8 will be fine? There are buds but I don't feel it will bloom, today I watered it and I saw few yellow leaves and 2 buds dropped, I was really disappointed , I think it is not getting enough light will grow light help in this case?

Thanks

Gardenias are acidic. I don't think the fertilizer in the soil is acidic. I prefer to just add a small amount to the top of the soil after planting. You can buy a small bag of acidic fertilizer. Is is usually labeled for azeleas. Wait until after it blooms to repot. It is ready, but it is not pot bound. Such a pretty plant. It will take alot of heat. Surprised the label said to keep it that cold. It is a tropical plant.

zackey,

Thanks for your advice about repotting, I was thinking the same way but wasn't sure.
I bought an organic soil for acid loving plants, and a fertilizer special for that purpose as well. Today I found some yellow leaves and 3 buds fell, I am watering it whenever I feel the surface is getting dry, usually every other day. But I feel maybe it is because not getting enough light? I ordered a plant light 60 watt will that help it? it is a fussy plant and will defiantly be a challenge keeping it healthy indoors

Thanks and I appreciate all the advices

Gardenias don't like drying out. You can even keep a bit of water in the saucer under the plant to make sure it stays well watered. No, they are not easy indoors--too dry for them and they get bugs. Mine are outside in pots in full sun, get hosed down daily, and go into a chilly garage over Winter. Indoors they are a pain, the cooler the better over winter btw, but no frost. I have one variety that IS cold hardy here in NJ, 'Frost Proof'. Some plants just want to be outside--this is one of them!