Rhododendrons are very hardy shrubs that many people like to keep in their gardens. If you have some of your own, you already know just how nice they are.
If your rhododendrons are having some problems right now, you might be a bit surprised. They’re so easy to take care of usually that you might not have expected to run into any issues.
When a rhododendron’s leaves are starting to curl, it might be worrisome enough that you’ll start looking for answers. Did you do something wrong or is the plant diseased in some way?
Read on to learn why rhododendron leaves curl so that you can understand what’s going on. You’ll also learn a bit about what can be done to fix any issues that it’s experiencing.
1 – Drought Issues
One of the most common reasons why rhododendron leaves will start to curl is that they aren’t getting enough water. If a rhododendron hasn’t been watered properly in quite some time, its leaves will begin to curl.
This is a big sign that your plant needs water, and you’ll want to give it a thorough watering as soon as you can. If your area has recently gone through a drought, that might be the cause of this problem.
Luckily, you can take things into your own hands and water it to help it become healthy again. Once a rhododendron is established, you should only have to water it every two or three weeks if it didn’t rain.
If the rhododendron is still new, it’ll need to be watered twice each week during the growing season. Don’t fret about the leaves curling if you know that it’s likely a watering issue.
2 – Too Much Water
Interestingly, too much water can also cause a rhododendron’s leaves to curl. You might have a rhododendron in soil that isn’t draining well, and this could make it so that it’s retaining too much water.
You can solve this by replacing the soil with soil that drains as well as possible. It’ll allow the rhododendron to dry out more in between bouts of rain or watering sessions.
If it continues to be exposed to too much moisture, it might kill the plant. It could cause root rot, and it might also lead to fungal issues.
3 – Fungal Disease
Fungal disease is another potential cause that you need to be aware of. When a rhododendron has a fungal disease, it’s going to get dark brown spots on its leaves.
Eventually, the leaves are going to start to curl, but the dark brown spots should appear well before that. You’ll need to take a look at the rhododendron to determine what is wrong, and if you notice brown spots, you’ll want to start treating it as soon as you can.
You can try to treat the rhododendron with fungicides to see if it helps, but many experts say that fungicides don’t seem to work. There are different types of fungal infections and some of them are harder to bounce back from than others.
Know that the best way to protect a rhododendron from something such as this is to prevent a fungal infection from ever happening. This means pruning leaves that show bad signs and not letting things get too moist so that fungi won’t be able to thrive.
4 – Getting Too Cold
Getting too cold is something that can cause a rhododendron to curl its leaves as well. During the winter months, it isn’t uncommon for cold wind to cause this plant’s leaves to curl.
Generally, the leaves will curl inward when the weather is cold in an effort to prevent water from evaporating from its leaves. You can help your rhododendron to make it through the winter by watering it properly.
When the temperatures are above freezing, it’s going to be good to give it a deep watering. This gives it enough moisture to work with so that it can survive.
Experts recommend giving rhododendrons water that goes about ten inches down. Watering them slowly with a steady drip of water is ideal.
The moisture will stay in the ground better if you place a few inches of mulch on top of the soil. If you do all of this, then you shouldn’t have to worry too much at all.
5 – Stems Breaking
Stems breaking can cause problems for your rhododendron, too. If you have stem issues, the leaves might curl due to not being able to get water.
The stem and branches carry the water up to the leaves, but if things break, then that’s not going to be possible. Sometimes stem injuries will occur due to heavy wind, but this can also happen during the winter months.
Heavy snowfall can easily cause stems to break on your rhododendron. It might be a good idea to try to clear off the snow instead of allowing heavy amounts to sit on your plant.
It might wind up being necessary to clip off certain parts of the foliage that have been damaged, though. If things don’t seem to be healing after a few weeks, it’s better to trim than it is to leave things alone.
6 – Insects
It’s even possible that insects could cause the leaves to curl. There are quite a few different types of insects that have been known to bother rhododendrons that you will want to look out for.
Weevils, lacebugs, leafminers, mites, and scale insects will all be potential problems. These insects will feed on the rhododendron’s leaves, and this can cause various changes to the leaves over time.
You might notice leaves changing colors or looking wilted due to the damage from the insects. If you don’t address this issue in a timely fashion, it could even kill the plant.
There are various control methods that will allow you to solve insect issues. You might need to use insecticide, but some insects, such as mites, can be blasted away with a garden hose.
Just do your best to be proactive if you suspect that your rhododendron has insect issues. You can save it, but you’ll want to take action soon so that it can continue to thrive.
Pay Attention to Your Rhododendron
If you pay attention to your rhododendron, it should be easier to take care of any issues. Curling leaves might be very concerning, but you can get it back to normal by troubleshooting what’s wrong.
It might be as simple as solving a drought issue or you might need to stop watering it too much. Fungal infections are also more common than many people realize.
Even cold weather has the potential to cause the leaves to curl, and you’ll need to prepare rhododendrons for winter. So long as you’re doing your best, it shouldn’t be all that difficult to get good results.
You now know all of the things that can cause a rhododendron’s leaves to curl. You know why this happens and what needs to be done to solve the various problems.
Keep enjoying your plant, but be mindful of what can go wrong. So long as you’re keeping your eye out for potential issues, everything will be just fine.
Growing up with a mom who filled her home (inside and out) with all sorts of plants, Lisa got her start in gardening at a young age. Living now on her own with a home and yard full of plants (including an indoor greenhouse), she shares all the gardening tips she’s gained over the years.