All plants react differently when they feel stress or threats to problems that affect their ability to survive. Cyclamen leaves curling is a response to a growing pain that the plant is experiencing.
The challenge is to identify the problem from a list of possible causes, and then put a fix in place. The plant will take care of the rest, uncurling its leaves as it relaxes into its normal growth stages without fearing for its life.
Note: These are likely causes to explore when you know that you have the basics nailed like watering, humidity, and lighting. If you aren’t sure, you may want to check out related resources:
Listed below are some of the trickier nuances that cause cyclamens’ leaves to curl.
5 Causes of Cyclamen Leaves Curling, Why it Happens, and How to Fix It!
1 – Mites
Cyclamens are prone to mite infestations.
The more common type to take up residence on this plant is the tarsonemus pallidus, more commonly called the “cyclamen mite”. However, it will readily traverse onto any other nearby ornamental flowering plants, such as chrysanthemums, African Violets, and petunias. It’s a yellowish-brown color and is not microscopic. Eyeballing the leaves is enough to spot these.
They hide out near the base of the plant on the underside of leaves. Cyclamen mites move faster than broad mites and spider mites. As they move around the leaves of the plant, webbing is left behind. The females are larger than males and they can drop up to 16 eggs each in their short life span. A heavy infestation of these can kill a cyclamen plant.
If you do find it hard to see these, the symptoms of the plant will clue you in on what’s happening. Mites on cyclamens cause the leaves to curl, or fold in, distorting the shape, and you may also notice shortening of the petioles.
Mites thrive in high-humidity environments and low-light conditions, which is why you’ll find them on the underside of leaves, near the base of the plant.
To kill the mites, their eggs, larvae, and pupae, completely immerse the plant in water that’s heated to 43oC or 110oF. and leave it soaking for 30 minutes. The heat will kill all life stages of the cyclamen mite.
Once they’re gone, you’ll notice the plant regaining its natural shape within a week to two weeks.
2 – Heat Stress
Cyclamens prefer cooler temperatures. Placed in areas of high heat, or exposed to direct heat sources like ducts or heaters, it can raise the soil or leaf surface temperature to over 70°F, (approx. 21°C), which is when cyclamen leaves curling becomes likely.
This is a behavioral trait of all plants. The only difference in why you see leaf curling in cyclamens and not others is that plants have differing tolerance levels.
As an example, hibiscus care indoors in the winter months may require a heat mat or small halogen fire to maintain temperatures between 60°F and 80°F. The leaves wouldn’t curl on the hibiscus because that can cope with the elevated heat indoors. In a room with temperatures exceeding 70°F though, the leaves on cyclamens would begin to fold inward.
It’s a survival thing. The hotter the environment the plant is kept in, the faster water evaporates. Leaf curling happens when the plant guards against evaporation. By reducing the leaf surface mass, less water can be lost to vaporization. Move it to somewhere cooler.
3 – Powdery Mildew
Powdery mildew is a fungal disease that is mostly concentrated on the leaf surface. The immediate symptom is the white spots coating the leaf surface and spreading. That’s quickly followed by leaf discoloration due to the photosynthesis process being restricted.
Fungi need nutrients for survival too. Just like mites, aphids, and sap-feeding pests can pierce the leaves of plants, powdery mildew fungi can latch onto a single leaf and use the appressoria to pierce through the cell wall and begin colonizing in the plant, not just on the leaf surface.
When the fungi spread from within, the plant will be drained of energy, sending it into survival mode. One of the symptoms displayed when plants are struggling to maintain energy levels is to curl their leaves.
At the first sign of powdery mildew on any plant leaf, the worst thing to do is just to dust it off and carry on as usual. You need to identify the cause (humidity, soil saturation, air circulation, etc.) correct the conditions the plant is growing in, and protect the rest of the plant’s leaves, and any companion plants you have around the infected one.
Once the fungi begin colonizing, rapid deformation is possible and can be fatal. If you see extreme deformities after seeing white spots on indoor plants, see our fixes for how to save a dying plant from diseases.
4 – Phosphorous Deficiency
Cyclamen plants, like any bloomer, require a modest amount of phosphorous to help it bloom. When the cause is a phosphorous deficiency, the leaf curling begins at the base of the plant, progressing upwards gradually. The oldest leaves are the first affected.
The most nutrients will be needed when the plant is in bloom. During its blooming phase, part of the cyclamen care requires it to be fed with a low-nitrogen, high-phosphorous feed every three to four weeks.
For those who live in states impacted by fertilizer bans, or in countries with fertilizer bans on imports, necessitating you to look for workarounds, banana peels are the solution for a homemade fertilizer for plants. Just be sure you don’t plant the peeling directly in the soil.
Soak banana peelings in water in a mason jar for a week then water the plant with that, or bake and grind it down to a fine powder to mix into your soil. That’ll provide it with a good dose of potassium, and phosphorous, as well as macronutrients of calcium, magnesium, and sulfur.
For the nitrogen, the simplest method is to make a grass tea mix – grass clippings steeped in water. You don’t need a lot for cyclamens as they don’t need much nitrogen.
5 – Poor Soil Quality
The quality of the soil is directly responsible for the health of the roots, and subsequently, the entire plant. Not all roots on cyclamens perform the same. The most active, in terms of nutrient absorbency – the ability to uptake nutrients in the soil and transport them throughout the plant – are long hair roots of around 3 cm.
Any roots longer than 3 cm are considered immature roots. They’ll remain stretching, corkscrewing, and curling in the pot or flower bed until they’re able to make contact with the soil. Until they do, roots search for an anchoring opportunity.
It is possible to have a super-developed root system on cyclamens, yet still experience a phosphorous deficiency. Only active and healthy roots can transport water-soluble phosphorous. Therefore, any overly thin, straggly, and long roots would be best trimmed so the plant focus on establishing more ‘active’ roots.
Loam-based and peat-free mixes work well work for cyclamens, and if you need to raise the pH slightly, mix in some sphagnum peat. Mature cyclamens do well in acidic soils with an acidity level of 6.0.
For cyclamen propagation, seed germination and root formation can be improved by potting up the seeds in a more acidic soil with a pH of 5.0.
The key things your base mix needs to provide the plant with are fast water drainage to prevent soil saturation (which can lead to root rot), and plenty of oxygenation because without oxygen reaching the roots, they can’t perform.
The roots are the machinery driving the growth of your plant. When things go wrong beneath the soil, everything up top goes wrong.
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.