How do I care for an indoor Gardenia?

Okay, so I bought a Gardnia plant a week ago, and I'm beginning to realize I'm in big trouble. It's not blooming even though it has about 10 buds on it. I've made sure the soil is moist, and it gets the right amount of sun. The leaves look wonderful, and it's about 3 1/2 gallons, maybe 2 feet high. It just doesn't want to open for me. The problem is, I live in the desert (Arizona), so could this be why it doesn't want to bloom? I do mist it every three days to give it some humidity. I take it outside at night for a couple of hours, but I don't leave it (it gets in the 50's). My dad, who has the worst green thumb, and has managed to kill every plant imaginable..lol.., managed to keep his gardenia alive. All he does is water it. Am I missing something?