I got a lilac plant last spring/summer and have kept it outdoors (zone 7) in its nursery pot. It is getting very cramped, with roots escaping from the drainage holes of the pot. One picture attached shows roots coming from a corner & center drainage hole. However, it's starting to grow leaves and even a few buds. Would it be better for the plant to transplant to a new, larger pot immediately, or to let it bloom in cramped conditions and repot when it goes dormant again? And if I do repot, should I go for a pot that is just a bit larger or a great deal larger?
Best to do it when it is dormant, but it could also be done after it flowers (but still cool -- i.e., not mid-summer). Others might have an opinion on pot size, I personally would only repot into something just a bit larger.
