Crepe Myrtle Not Blooming?

I have a very large Crepe Myrtle that doesn't bloom much, but it's very tall and not bushy at all. What's the problem. My other Crepes didn't bloom much this summer either.

Hardiness Zone: 7b

Shelah from Spring City, TN

Answer:

The number one most common reason Crepe Myrtles fail to bloom is improper pruning techniques (or a lack of pruning altogether). Crepe Myrtles bloom on the current season's growth. If they are pruned too late, all the new wood is removed and the flower buds never develop. Pruning should be done only after the tree flowers. You said your tree is very large so it may be older. Declining Crepe Myrtles can be revived by pruning. In the dormant season, some of the extraneous branches are cleaned up and removed, opening the interior of the plant to more sunlight and air circulation. Be careful not to commit "crepe murder." Just cut the branches to enhance the natural, overall appearance of the tree, don't whack them all back to one height.

The second most common reason Crepe myrtles fail to bloom is a lack of sun. These trees need a lot of sunshine if you want them to bloom. Are there any trees nearby that may have grown up and around your Crepe myrtle and are blocking some sun?

Is your tree otherwise healthy? Do you see any signs of insect damage or disease? Stress from either can be enough to prevent your tree from blooming.

Is your tree getting too much nitrogen or not enough phosphorus? Trees in the middle of a chemically treated lawn or near garden beds that are heavily fertilized may be getting too much of a good thing when it comes to nitrogen. This promotes healthy leaves, but inhibits flowering. Try adding a little bit of bonemeal as mulch around the tree. This will add phosphorus to the soil over time and you don't have to worry about overdoing it.

Ellen