Crepe myrtle has placed itself in people’s hearts as well as in most of the garden lots with its charming blooms. This tropical beauty is native to the temperate zone. So, it’s a bit tricky to grow them in other regions.
Though crepe myrtle is resistant to several weather conditions, this plant easily gets affected by some unwanted injuries. Most of these start with leaf symptoms and leaf curling is one of them.
Now the question: Why are the causes of Crepe Myrtle Leaves Curling?
The most common reasons for leaf curling in crepe myrtle are Pest infestation, viral attack, nitrogen imbalance, environmental stress, and chemical damage.
Hope this article will help you to take a deeper look at these issues and provide you some effective options in such a case.
So, let’s get started without further ado-
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Common Causes of Crepe Myrtle Leaves Curling & Solutions
1. Pest Infestation
For the plant leaf curling, pests are one of the most habitual intruders to blame. They suck up the sap from tissues which results in crinkled leaves.
So if you ask me only one main cause of crepe myrtle leaves curling and drying, I can simply advise you to check pest activities on the first note. And the most harmful insects for Crepe myrtle are aphids, spider mites, whiteflies, and thrips.
By observing your plants, you can trace these little evils. Aphids, whiteflies, and thrips are mostly found under the lower leaf surface with some black deposits. Thin webs tangled in curled leaves indicate the presence of spider mites.
Sometimes you may observe that crepe myrtle has a sticky feel and the leaves are curling. This is because of insect feeding and residues like honeydews.
As crepe myrtle is a bushy shrub, it’s a bit tricky to individually search for all these insects. Here I have provided an overall instruction on controlling these pests. So, let’s take a closer look.
Spraying a good splash of water can displace these pests and also remove any webs and residue. So, try this easy method first.
Try some neem oil, canola oil sprays, insecticidal soap, or any other insecticide. These will effectively remove pests with lower chemical usage. (our pick: Garden Safe Neem Oil Extract Concentrate)
If the infection has spread to your flower buds, include a systemic insecticide. I have an easy pick for you. (Our Pick: Bonide Insect Control Systemic Granules)
Insect control spikes are another good option to control infestation as these protect plants for up to 8 weeks. But be careful about the time of application. Avoid applying these spikes until blooming has completed in your crepe myrtle.
#Recipe 1: Alcohol Spray
- 5 liters of 70% isopropyl alcohol.
- 10 liters of water.
- Mix water and alcohol as a mentioned ratio.
- Shift the solution to a lawn sprayer and apply it to your foliage.
#Recipe 2: Herbal Water Spray
- Sage, thyme, basil, and rosemary leaves.
- A bucket of water.
- Crush all the leaves together.
- Add water to this mixture.
- Soak water and crushed leaves overnight.
- The next morning, strain and apply this solution to your plant with a garden sprayer.
Keep in mind that you have to protect your plants from harmful insects, not from the beneficial ones. Preventing some types of insects can hamper pollination. So here are some of our suggestions to balance between.
Pamper your garden with some gorgeous petunias. These easy maintaining plants are a good repellent to aphids. It’s also a good deal if you can find venus fly traps for your garden. These will lure whiteflies and thrips without killing the useful insects.
2. Viral Attack
Viral infection is quite common in crepe myrtle diseases. If you notice upward and downward curling of your plant leaves with some thickening mass, this might be the result of a viral attack.
Viruses can transmit via insects, nematodes, and mites. Specifically saying, leaf curl virus is the main culprit.
It’s quite hard to cure a viral infection. However, some management practices can effectively reduce disease severity in your plants.
Insect acts as a vector of viral diseases. So, you must get rid of insects from Crepe myrtle.
Trap cropping is a wise decision in controlling insect vectors. In this process, you can place some other plants that will drag harmful insects. As mentioned before venus fly trap or some beautiful marigold blooms may be a good pick.
Another necessary step is soil fumigation. This will reduce soil-borne hosts for the virus. A nematicide may also help in crucial conditions.
3. Nitrogen Imbalance in Soil
Nutrients play an important role in plant overall growth. And this is why nutrient imbalance symptoms are quite prominent. Mostly these symptoms start with plant leaves.
Unhealthy leaves are a common symptom of nitrogen deficiency. If you notice that your crepe myrtle older leaves are curling and turning brown, the most obvious reason can be this sort of deficiency. You’ll be surprised to know that even excessive nitrogen causes your leaves to curl up.
In this case, most of the nitrogen diverts directly to the newer leaves and thus the older ones succumb by curling up. The associated symptoms can be leaf yellowing and drying. Intensely green and thick rolled leaves are the result of excessive nitrogen application.
To balance the nitrogen level in the soil you can follow our suggestions. So, let’s get started.
First of all, test your soil to check the nitrogen level. Three to six ppm is considered to be normal. You may need a soil testing kit, as there is no other way of checking your own.
Then pick a fertilizer according to your needs. You can choose a balanced NPK fertilizer that will solve other nutrient issues as well as nitrogen deficiency. (Our Pick: Nelson Crape Myrtle & All Flowering Plant Food)
Let’s talk about a little drawback of these fertilizers. These may boost up nitrogen levels in your soil fast, but the effect won’t last that long. That means the repeated application is needed quite often.
So, what can you do if you wish to avoid such frequent applications?
Well, I can recommend using compost manure as a substitute. You can directly apply some or plant some nitrogen-fixing crops like peas or beans in your garden.
This method needs a longer time to cope up with the deficiency. So, if you are in urgent need, go for the fertilizer option.
#Recipe 1: Coffee Ground/ Tea Mixture to add nitrogen to the soil
- Coffee ground/ used tea leaves.
- Wash your leftover coffee grounds or tea leaves with fresh water.
- Put these to your soil as per need to add nitrogen in the soil.
#Recipe 2: Sawdust to reduce nitrogen level in the soil
Add sawdust to your soil. This will potentially reduce excessive nitrogen in the soil.
4. Stress Condition
Improper watering, excessive light, and heat damage can push your plants to stress conditions.
While under watering hampers the overall growth of plants, overwatering damages the roots causing potential strain which leads to inward curling in plant leaves.
Mostly in summers, your plants can get a heat shock more often. Excessive heat increases stomatal respiration. In such a situation your plant leaves curl inwards to protect them from further damage.
Leaves turning brown with curling and shedding off are common symptoms of stress in the plant. So, if you observe your crepe myrtle leaves curling and falling off in some scorching hot weather, probably it’s time to take steps to prevent this type of stress.
Some easy practices can easily reduce these stress conditions. Let’s see how these work.
First of all, plant your crepe myrtle in such a place where there is partial sunlight available. A corner of your garden or side plantation may be effective. This will protect your plant from direct sunlight for a long time.
Prune your branches often to provide proper air circulation. Doing such will help to reduce heat damage quite a bit.
Last but not the least, keep an eye on your watering schedule. Don’t over water your plants. Also, don’t ignore the soil moisture level too. It’s better to keep checking your soil. A soil moisture meter can help you if you can’t determine on your own.(our pick: Atree Soil Soil Tester Kits with Moisture, Light, and PH Test for Garden)
5. Chemical Damage
Chemical damage is generally caused by herbicides used to control broadleaf weeds. Gardeners mostly use phenoxy herbicides to control such weeds. You might have been using these too.
It’s proven in a study that herbicides like Dicamba and 2,4-D cause leaf curling in ornamental plants like crepe myrtle. This occurs when your plant leaves come in direct contact with these herbicides.
To avoid such damage be careful while using these herbicides. Don’t let your foliage to come in contact with these.
Practice some good cultural methods for a healthy lawn. Mowing can be practiced to destroy broadleaf weeds without frequent herbicide usage.
These easy executions may help to reduce any chemical damage as well as herbicide injury.
I tried my best to cover most of the issues related to leaf curling problems in crepe myrtle. So, if you are struggling with this problem and thinking of how to revive your crepe myrtle this may help you.
Remember; don’t go overboard with any practice. Just check for pest and viral infection, provide a balanced nutrient, and try to skip the stress conditions as much as possible and you are good to go!
I am eagerly looking for your feedback. So, don’t forget to share your ideas with us. Happy growing!