Best time to re-pot a plumeria?
My mom has half a dozen 3-5 gallon plumeria trees that I feel desperately need to be repotted. The soil (I think it's native clay "dirt" and not even cactus mix or anything) has sank 8" below the lip of the pot and some of them weren't rooted with a support and don't stand straight. Despite the neglect, they are "Gardena" and didn't go dormant this warm winter.
When is best to repot, does it matter? Id hate to kill her trees.