ZZ plants are known for their low-maintenance nature, so it’s a bit alarming when you find odd symptoms like leaves curling or dark edges. You’re probably wondering: why are my ZZ plant leaves curling?
ZZ plant leaves may curl for several reasons. These reasons include exposing the plant to excessive sunlight, incorrect watering techniques, and pest or insect infestations. Most of these factors are easily corrected. The key is to identify and address the issue early.
Read on to learn more about the factors that cause leaf curling in ZZ plants, as well as how to solve the problem.
Overview of the ZZ Plant
The ZZ plant is a perennial that’s native to the tropical region of East Africa. Many homeowners choose to grow ZZ plants in their houses due to their exotic aesthetic. The low-maintenance nature of these plants is another reason why they’re so popular.
ZZ plants can grow in various conditions and are popular for their tolerance to low water and light conditions.
These plants can grow to an average height and width of three feet. However, you’ll need to be patient to see your ZZ plant get that big. A typical ZZ plant will take four to five years to reach its maximum size.
Why Are Your ZZ Plant Leaves Curling?
If you’ve noticed that your ZZ plant’s leaves are curling, there are several factors that may cause this. They revolve around the plant’s growing conditions and how well you take care of it.
Here are some common causes of ZZ plant leaves curling:
1 – Excessive Sunlight Exposure
Exposing a ZZ plant to too much sunlight is often the cause behind its leaves curling.
The ideal light condition for ZZ plants is moderate indirect sunlight. When you expose these plants to excessively direct sunlight, their leaves will curl in an attempt to shield themselves from the light.
Brown burn spots on your plant’s leaves are an indicating sign that excessive sunlight is what’s causing the leaves to curl.
How to Fix it
The first thing you should do is change the plant’s location immediately. Move it to a spot that’s far from the window so it gets less direct sunlight. You can also install blinds or curtains so the light reaching your plant is indirect.
If you have no option but to place the plant next to a window, it should be an east or west-facing window. This is because south-facing windows tend to bring in intense light.
Don’t expect the brown burn spots on your plant’s leaves to disappear once you move it. You should carefully trim the affected areas of the leaves.
2 – Insufficient Watering
As previously mentioned, ZZ plants are extremely tolerant to scarce moisture. However, that doesn’t mean that you should neglect to water them altogether. These plants still have a minimum water requirement so they can function properly.
Underwatered ZZ plants will curl their leaves to try and maintain moisture.
How to Fix it
Before taking action, you should confirm that underwatering is what’s causing the leaves to curl. You can do so by watering the plant slightly more often and checking if the curling is gone.
Once you’re sure insufficient watering frequency is the culprit, you should start altering your watering schedule. We recommend watering once every four weeks in winter and twice a month in the summer.
An effective way to gauge when your ZZ plant needs watering is to use your index finger to push the soil and see if it feels dry.
3 – The Temperature Is Too Low
Another possible cause of leaf curling is the surrounding temperature being too low. In their natural habitat, ZZ plants are accustomed to warm temperatures between 65 and 85℉.
If you leave your ZZ plant in excessively cold conditions, the leaves will start to curl. The curling starts to be noticeable at temperatures below 50℉.
It’s not only consistently cold temperatures that cause leaf curling. A sudden change in temperature can also cause this as the plant goes into shock.
How to Fix it
To prevent curling due to cold temperatures, place your plant away from sources of cold air. These sources include fans, windows producing cold drafts, and AC vents.
4 – Insect and Pest Infestations
Your ZZ plant’s leaves may also curl because of pests and insect infestations. ZZ plants attract various pests, such as aphids, mealybugs, and thrips. These pesky critters feed on the plant’s sap, taking nutrients away from the plant and causing its leaves to curl.
If left untreated, such pests cut through the plant’s leaves, making them prone to disease and ultimately, death.
How to Fix it
To identify whether pests are what’s causing the deformities in your ZZ plant’s leaves, you should use a magnifying lens to inspect the leaves for signs of piercing.
If you’re sure there’s an infestation, you should separate the affected plant from the others instantly to prevent the infestation from spreading.
Next, treat the infested plant with insecticidal soap and neem oil to kill the existing pests and deter future ones from plaguing your ZZ plant.
5 – Excessive Watering
Just like ZZ plants don’t fare well in excessively dry conditions, they also don’t do well in cases of too much moisture. Constantly having your ZZ plant in soggy soil can lead to leaf curling and many other issues.
The underlying cause is root rot. This condition involves your plant’s roots suffocating and not being able to transfer nutrients from the soil to the plant itself. As a result, the leaves curl, and the plant’s stems turn brown and mushy.
How to Fix it
If you’re unsure of how often to water your ZZ plant, it’s better to risk watering it too little than too much. Underwatering is easily remedied while overwatering can be fatal to your ZZ plant.
You shouldn’t water your plant unless the top inch of the soil is completely dry.
Additionally, make sure to place your ZZ plant in a container with good drainage. We recommend pots with built-in drainage holes. You can also go the extra mile and improve the soil’s drainage by adding perlite to the mix.
6 – Your ZZ Plant Is Rootbound
Another occasion in which your ZZ plant’s leaves will curl is the plant being root bound.
These plants grow from rhizomes, which are underground structures that act as water and nutrient storage for the plant. As the plant grows, its rhizomes need room to grow. When rhizome growth is inhibited, a ZZ plant’s leaves will start to curl.
The most common cause of a rootbound ZZ plant is its pot being too small.
How to Fix it
If your ZZ plant has become rootbound, the best way to correct this is by moving it into a larger pot so the rhizomes have room to expand. You can tell that it’s time to do this if your plant’s roots are visible on the soil’s surface.
We recommend using a pot one size larger than the previous one. You should also make sure that you have well-draining soil in the new pot. The repotting process is stressful enough for your plant as it is. You don’t want to make it worse by risking root rot.
7 – Incorrect Fertilization
Your ZZ plant’s curled leaves may also be a product of incorrect fertilization. This applies whether you use too much or too little fertilizer.
Using insufficient fertilizer leads to your plant not getting enough nutrients. As a result, its leaves will curl for energy conservation.
On the other hand, excess fertilization can damage your plant’s roots, and this also causes leaf curling.
How to Fix it
To fix this issue, you should use a more suitable fertilization schedule with reasonable quantities.
We advise against using fertilizer on your ZZ plant in the winter. During summer, it’s best to apply high-quality fertilizer to your plant twice a month.
Final Thoughts
If you’re wondering why your ZZ plant leaves are curling, there are many possible answers.
The state of your plant’s leaves may be a product of overwatering, underwatering, excess sunlight, or the plant being root bound.
Once you know what’s causing your plant’s leaves to behave this way, there are simple measures you can take to resolve the issue.
Use the tips and tricks discussed in this guide to keep your ZZ plant healthy for years to come!
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.