Hi! My sister gifted me a gardenia bonsai for my birthday, and it arrived this morning. I am totally new to the bonsai world. I am in Yuma, AZ (10a), so I am guessing indoor is best, since it reaches around 115 most days in the summer. It came in a black rectangle pot with a tray and a bag of grey rocks. What are the rocks for? I am assuming to put in the bottom tray, but wanted to make sure. I have it in my bedroom where it receives bright light, no direct sunlight. Is that sufficient? Should I put it outdoors during our mild winters (never gets below 32F).