I had a mandevilla last year and garaged it over the winter, in spring took it out and waited and waited no green! so i dug it out of the pot and found fifteen tubers on this thing! did i jump the gun? would it have come back if left for a while? or do they need to seperated and left to rest until next year? if so how best to seperate them? any advice and or knowledge would be appreciated! thanks in advance.