Answer: I have had the same problem and I am experimenting on different solutions. Season before last, I tried two different things and I did see more bloom this past spring/summer than seasons past. The first was pruning. I pruned out some inner branches so more sunlight could get within the tree. I removed branches that crossed, seemed weak, touched one another, or were simply too close to each other. The second is feeding the tree. In the spring, I "top dressed" the tree with quite a lot of compost, all the way out to the drip line of the tree. I applied a layer about 3" thick. I also gave the tree a bit of 5-10-10 fertilizer (follow package instructions). As I mentioned, this did help. I plan to do the same thing again this year (though I shouldn't need to prune much more).
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