Ask-a-Dave's-Gardener: Plumeria leaves browning and falling off, 2 by adinaschild

adinaschild wrote:
My in-laws bought us a Plumeria plant. We live in Toronto, Ontario (Canada) and it is now close to the winter time. The leaves are starting to brown and fall off. I only water the plant once every two weeks. The plant has always been in my home in an eastern facing window. It had leaves growing nicely all summer (since potted) but now they are starting to brown and fall off. I just want to make sure that we are not killing this poor plant.
Any help would be greatly appreciated.