I have kept mandevilla with mixed success--one year they made it through fine, the next year they made it to March then succumbed to something (a pest?). Another year they were clearly infested with something that I could not control & they died by February. I kept them near a southern window & watered about every 5 days, & did not feed. If I try it again, I will be more aggressive about cleaning the plant before I bring it in.