Answer: These trees are fairly reliable bloomers, but your area has had terrible drought stress and some late cold snaps this spring. It is possible that they did not form flower buds last year, or if they did, the buds may have frozen right before opening this spring. I am a little north of you and the heat wave last week destroyed the blossoms on my tree, they lasted just one day. Let's hope for better weather next year. Finally, badly timed pruning could also remove flower buds; in general this tree does not require any routine pruning. I hope this helps you trouble shoot.
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