Well it’s happening again … many of the leaves on my azaleas have turned yellow. So as I did last year, I’m briefly interrupting our holiday-related posts to re-post the answer to a question that I’ve had…and one that several of my clients have asked me recently … Why are my azalea leaves turning yellow?
It seems that every year around this time a disproportionate number of my azaleas’ leaves have turned yellow…and the bright yellow really stands out because the only other colors going on in my yard are green and brown. So what’s up?
Since I’m pretty much a self-taught landscape designer (i.e., I don’t have a degree with anything plant in it), I wanted to make sure that I was complete and accurate with my answer…so I reached out to my all-around-plant-guru-friend Holly Brooks from King Landscaping. And here are three potential answers we’d like to suggest…and what you should do about it, if anything.
- There’s nothing to worry about at all, they’re just molting…losing their leaves. Even evergreens lose their leaves…just not all at once like deciduous plants do. Azaleas set their leaf buds in the fall…and the emergence of these buds prompts molting. Having random yellow leaves scattered throughout your azaleas is normal…these leaves are simply molting. There’s nothing you need to do or worry about. Just wait for new growth in the spring.
- There’s nothing to worry about…they may just need to be fertilized – but wait. It may be that your azaleas are just needing a little bit of extra juice…particularly nitrogen. Nitrogen-deficient azaleas seem to shed even more leaves…hence more of them turn yellow. But don’t run out and fertilize them now … wait until the spring. If you fertilize them now it may cause them to start producing new leaves … which you don’t want, because this tender new growth would likely be burned during the winter’s cold weather. Just enjoy your yellowy garden, have patience, and rest in knowing there’s nothing you should do now.
- However, there could be an insect issue. Silvery and yellow mottled or even bleached-looking leaves indicate a potential lace bug infestation … one of the most common pests to azaleas. If you can’t tell whether the leaves are molting or have an insect problem, simply look at the underside of the leaves. If it seems like there’s crusty dirt, you have lace bugs … but it’s not dirt, it’s bug feces…lovely! And if you do, you need to act fast…lace bugs are active breeders so a small problem can quickly become a big problem. So spray them with insecticidal soap … making sure to drench the underside of the leaves.
Fortunately for me … there’s no dirt on the underside of my azaleas’ leaves … so it’s just the normal molting process. I’ll simply wait for their normal burst of flowers and new leaf growth in the spring. Now, I may throw out a bit of nitrogen-rich fertilizer after the last frost of the year just to be on the safe side to hopefully minimize all the yellow next year. We’ll see.
I hope this post has helped any of you who have ever wondered why are my azalea leaves turning yellow.
Take care all,