Q: One of my four azaleas is starting to lose the green color of the leaves. They are turning yellow from the bottom up. The other three bushes have retained their full green color on all leaves.

Do you have any ideas what this could be?

A: It’s normal for azaleas to have a lot of yellow leaves at this time of year. The usual pattern is a tuft of green leaves at the end of each branch with older yellow leaves in the interior of the plant.

But that’s not your case. The yellow leaves on your azalea are concentrated in one part of the plant while the rest of the shrub looks green and healthy.

This symptom tells me that the root system is impaired or there is a marked pH difference on that side of the plant.

I can’t determine how the water flows there but soggy soil would be a common cause of root deterioration. Use a trowel to dig out the existing soil beneath the yellow section and replace it with high quality bagged planting soil. Water it in with a half-strength solution of houseplant fertilizer.

NOTE: Pat B. at Living Fences suggests that it could be the “dreaded canine canker” i.e. a dog is visiting this azalea regularly.

normal winter yellowing

normal winter yellowing