Mountain Laurel Brown Leaves

Asked September 8, 2019, 3:39 PM EDT

I have 5 mountain laurels that have been in the ground for about a year and a half. They have been doing fine and bloomed this spring. This summer the leaves started turning brown and completely killed one of them. Why do you believe this is happening, and what should I do to help the remaining 4 plants that have some brown leaves?

Montgomery County Maryland shrubs mountain laurel brown leaves

1 Response

In general mountain laurels can be difficult to grow in our area. They do not like our heat and humidity. They can also be susceptible to fungal leaf spots. Cleanup all fallen leaves and old leaf debris below the plants. They grow best in an acidic moist well drained soil in morning sun and afternoon shade.

It is possible you may be dealing with a root issue but cannot say for sure. We notice a downspout in the photo. Make sure it is not dumping water in the root zone. If so, the plants will be susceptible to root rots. Check the drainage in the area. Last season we had abnormal rainfall and this spring was also wet. If the soil is heavy clay, this can limit oxygen in the soil and affect the roots.

At this point, check the drainage and make sure mulch is no thicker than several inches and away from the base of the plants. Water during dry periods. Prune dead wood and monitor for new growth next spring.
Here is more on mountain laurel http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=c798

Marian