Tropicals & Tender Perennials: Who is she?, 1 by mstish

mstish wrote:
I was given this standard. The tag called it a potato tree, Solanaceae. I’ve had her for about 3 years. I haven’t been able to find much out about her – searched the web and found things similar but nothing that was a match. She has one inch purple blooms and in the winters about half of her leaves fall off. She spends her summers outside in full sun and the winters in front of a window. I haven’t given her any fertilizer because I don’t know what she likes.

Can any of you tell me what she is and how to care for her.