Q.why did my Redbud tree not leaf out this spring
It does not look dry or dead, but no leaves. Some are starting at the base like suckers but none on the tree. I planted it in the fall and watered until frost. The branches look good and strong and alive but no leaf buds or leaves.
Do the branches bend or break and snap off?
It is most likely that your newly planted tree did not survive the long harsh winter that nearly the entire United States suffered this past year.
The growth the you are seeing at the base are most likely growing from the root stock and are of a different tree origin most likely.
Most garden centers or nurseries will replace a tree in the first year if it does not survive.
It sounds like you used the proper care of the tree.
Here is a few links.
https://www.gardeningknowhow.com/ornamental/trees/redbud/caring-for-redbud-trees.htm
https://www.gardeningknowhow.com/ornamental/trees/tgen/watering-newly-planted-tree.htm
