Some years my tree is covered with beautiful dark pink blossoms, and other years no blossoms. What is the difference?
Certified GKH Gardening Expert
There can be several reasons your seeing more or less blossoms.
First, your tree may be a alternate-flowering cultivator. The tree normally produces many blossoms one year and less the next year.
Drought can cause the tree to stop flower production to help the tree regain it's energy.
Disease can weaken a tree so that it can't support flower production.
Here is an article with more information.