The last couple of years I have purchased a mandavila plant they are very buitiful and showy. I have not been able to keep them for more than a couple of months. They just start top wilt and die. What am I doing wrong. I know thwey can be grown here in summer becaus I go to a park and they have them growing in pots like I did.

Purchased Mandavila and had one bloom and sofar no other blooms have appeared, Why? What do we need to do?
Jo