Experts and BHG readers answer.
weeping Cherry Tree
If all the new growth is coming from below the graft union, you may not be able to salvage the weeping form of the tree. If, on the other hand, the growth is coming from above the graft union, stake or train the new shoot to grow upright as tall as you'd like the tree to be. Then allow the new growth to naturally cascade to develop a new weeping crown.