Azalea from Brussels bonsai in Mississippi. Possibly a satsuki azalea, since that's what Brussels has. In a climate (please add your location in your avatar to the left) like yours, best to keep it indoors this winter. Some satsuki varieties are more cold hardy than others, but -30 F will probably kill the hardiest of them. That means you have an overwintering challenge. You have to find a bright, humid, but not necessarily warm place inside for it. Also, an unheated garage is risky with Satsukis. Had a friend here in Va. who lost a few after overwintering in his garage. Didn't kill them outright, but significantly weakened them over a couple of years. I have a feeling it was the lack of adequate light in that situation.
Also repotting azaleas is not as straightforward as other more forgiving species used for bonsai. you have to be a little less aggressive with the root mass--roots break easily.
Learn everything there is to know about Satsuki Azalea Bonsai, their origin, care information, where you can purchase one of your own, and more.
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repotting
Azaleas are well-known for having two repotting seasons - one at the end of winter before the spring growth emerges, and one after the flowers bloom in late
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