I recently repotted my weeping cherry tree seedling. It's only a foot tall, and I thought it was dying, so repotted it in hopes that that would help. Well, it did and now it has blossoms on the branches. Is this normal?
How Often Do Weeping Cherry Trees Bloom
Plants that are under extreme stress will often react with producing flowers -- sort of a "hail mary," from the plant's point of view. Also, your tree is a toddler, and young plants often do things older ones wouldn't. So, not too unusual. I hope you'll be able to correct the conditions that led to the tree's losing all its leaves -- most likely, not enough water. Here are 2 articles that should be useful, one on weeping cherry, and one on growing trees in containers.