What is this on my Azalea

Asked August 17, 2017, 1:28 PM EDT

I have three Azaleas planted in early spring that were blooming and healthy with new growth until about 5 weeks ago when they started developing brown dry spots on leaves. I am attaching picture. Any idea what this might be and what to do to support these plants. Thank you.

Montgomery County Maryland

1 Response

We viewed your photos. We notice that the leaves look scorched and also looks like there is a lack of establishment. When plants are planted within the first year of planting they are not usually subject to disease and insect issues.
It is usually poor planting techniques, poor drainage, planting too deeply, too much mulch, etc. Take a look at our publication on these types of problems http://extension.umd.edu/sites/default/files/_images/programs/hgic/Publications/HG86%20Common%20Abio...

You did not mention where the azaleas are planted - sun versus shade. They grow best in morning sun and afternoon shade. Foliage will be scorched in afternoon sun
and the plants will be susceptible to a sucking insect called lace bugs. If the plants are in full sun, you should transplant to another location.

Also, if the plants were container plants the root system can be root bound within the container. If not spread out, the root system may not be able to penetrate into the native soil. It can be difficult for water to get to the roots.

You can tug on the root system of the plants. If the plant pulls up easily, you may be able to lift the plant and tease apart the root system and replant. Do not plant too deeply and make sure mulch is no thicker than several inches and keep away from the base of the stems. Here is more information about the planting process and container plants.

You will have to check the soil moisture of newly planted trees and shrubs about once a week for the first two growing seasons until the root systems get established. Soil that is moist or damp to the touch is fine. You may need to probe with a screwdriver. If the soil begins to dry out, water the plant deeply. Do this up until the ground freezes. Do not overwater.