I have a Dieffenbachia houseplant that has grown to over 6 feet tall. It is beautiful and I want to do whatever I can to keep it healthy. The problem I'm having is the stalk/cane has become weak and will not stand up straight. It does not have yellow leaves; in fact, it continues to produce new leaves. What advice does anybody have for me? I would appreciate any ideas. (Certain members of my household have suggested lopping it off at the base and starting over!)Thank you!