Hello. I have (had) a beautiful Wisteria that developed flower buds then stopped. I have left it for about a month hopeing that it would pick it's self up but to no avail and today I chopped it down. The inside of the main stems have brown speckles through them but the actual wood is still green and healthy looking. A new plant has come up from the base but I suspect that it is from one of last years seeds. Does anyone know what can cause this and how to prevent it in the future?