Why Do Rhododendron Leaves Curl During Winter?

Take a close look at the photo to the left (you can click on it to see a larger image). Is this a sick rhododendron? Is it doomed to a terrible fate? Nope, it’s just a very cold rhodie that is doing what it can to get through our cold winters!

This doesn’t happen to all rhododendrons, though. When my husband and I bought several of them for the beds next to our front porch, we were very careful to choose the hardiest cultivars we could find.

This particular cultivar (wish I could recall the name!), really curls its leaves when the temperatures drop. But others don’t curl their leaves at all. We’ve noticed the common denominator with those rhododendrons is that they have larger, wider leaves. Perhaps they’re more cold-tolerant?

So why do some rhodies get curled leaves? It’s actually a natural mechanism that protects the leaves from being too exposed to cold temperatures. Once the weather warms up a bit, the leaves will return to their normal appearance.

However, if you happen to see this taking place during the summer months, that means the plants are not getting enough water, so you will want to take immediate action!

I should also mention that during the growing season, if you see curled, distorted leaves –along with some chewing damage — that is likely caused by a leaf roller which is a type of caterpillar. The best resolution to that problem is hand-picking of the damaged leaves since the caterpillar is likely inside.