Crape myrtle never blooms except after pruning in winter

[themetallurgist]

I'm wondering why my crape myrtle never blooms. It hadn't bloomed in years so I decided to trim in 2 winters ago. The next spring it bloomed like crazy. I didn't trim it this past winter because I shouldn't need to to get it to bloom, so this spring it did nothing and got no blooms. Do I just need to trim each year? It gets plenty of water and full sun. I feed the grass around it with nitrogen. I recall putting fertilizer spikes in one or two years before and dont recall it doing much. Maybe it is getting too much nitrogen and not enough phosphorous?

 

[Chuck]

I'm wondering why my crape myrtle never blooms. It hadn't bloomed in years so I decided to trim in 2 winters ago. The next spring it bloomed like crazy. I didn't trim it this past winter because I shouldn't need to to get it to bloom, so this spring it did nothing and got no blooms. Do I just need to trim each year? It gets plenty of water and full sun. I feed the grass around it with nitrogen. I recall putting fertilizer spikes in one or two years before and dont recall it doing much. Maybe it is getting too much nitrogen and not enough phosphorous?

If the tree is healthy a phosphorus deficiency is probably the cause. It won't be an instant fix but if you remove any grass from a radius of about 4 feet, cover with compost and mulch and then fertilize with added fish meal or bone meal it should take care of the problem. Do not fertilize the tree with the same stuff you are using on the grass. I would use Medina Grow N Green. It is what I use on my CM and mine blooms like mad. The Medina works wonders on grass too.

 

[themetallurgist]

If the tree is healthy a phosphorus deficiency is probably the cause. It won't be an instant fix but if you remove any grass from a radius of about 4 feet, cover with compost and mulch and then fertilize with added fish meal or bone meal it should take care of the problem. Do not fertilize the tree with the same stuff you are using on the grass. I would use Medina Grow N Green. It is what I use on my CM and mine blooms like mad. The Medina works wonders on grass too.

Thanks chuck! I have 15-10-15 that I will fill in little augered holes around the tree in early fall. I'd hate to dig up all the nice zoysia around it. Hopefully that does the trick. I will probably do a bit of pruning again this winter.

 

[Chuck]

Thanks chuck! I have 15-10-15 that I will fill in little augered holes around the tree in early fall. I'd hate to dig up all the nice zoysia around it. Hopefully that does the trick. I will probably do a bit of pruning again this winter.

The feeder roots extend out to the drip line and in all areas inside that line. Are you giving all of the feeder roots feed by drilling some scattered holes? And are you feeding any of the feeder roots that are deep or are the roots of the grass getting most of the nutrients? I fertilize my tree right before bud break before new growth begins. Pruning too late in the season disrupts the growth of new wood which buds and blooms form on. If you must prune a CM do it right after it blooms. The only reason IMO to ever prune a CM is to remove dead wood and possibly low hanging limbs or limbs growing the wrong direction. And cosmetically to remove seed pods.