Peperomia plants are small, compact, and easy to maintain, which makes them excellent indoor plants. However, the attractive foliage of the plants can sometimes become curled, yellow, or drooped.
Peperomia leaves that are curling, drooping or falling are caused mostly by overwatering, as the roots get damaged and cannot deliver water and nutrients to the plant. Additionally, these foliage problems can also arise from nutrient deficiencies, light and temperature stresses, pests, and diseases.
However, curling, drooping, and falling leaves can be corrected or stopped, and this article discusses ways to do so.
Different Kinds of Peperomia Plants
Peperomia, also known as the radiator plant, is a large genus of plants from the Piperaceae family with over a thousand species. Peperomia plants are native to Central and South America.
Radiator plants are common houseplants, popular because they are easy to grow and for their attractive foliage. Common examples include:
- Watermelon Peperomia (Peperomia argyreia)
- Ivy-leaf Peperomia (Peperomia graseoargenta)
- Beetle Peperomia (Peperomia quadrangularis)
- Baby rubber plant (Peperomia obtusifolia)
Reasons Why Peperomia Leaves Are Curling
Curling leaves is a frequent complaint of Peperomia plant owners. There are several reasons for this: overwatering, poorly drained soils, light, and temperature fluctuations.
Peperomia plants do not require much water, as excessive watering causes leaf curling due to root rot. Watering can sometimes be tricky, as various factors like humidity and temperature may affect the plants watering needs. Also, Peperomia plants require even less water during the colder months of winter, as the plants have gone into dormancy.
Consequently, it is best to water the plant only when the soil is almost dry. You can check the soil’s moisture content by merely pushing a finger into it to feel for the water.
Poorly Drained Soil
Poorly drained soils will eventually lead to root rot, as the water remains in the soil for too long, thus depriving the root of oxygen. The peperomia leaves will curl in response, as the rotten roots can no longer deliver enough water to the leaves.
Most peperomia plants are small epiphytes that grow on rotten wood, and not in soils. Consequently, the right soil for indoor peperomia is quick draining to ensure that water does not remain in the soil for too long.
A mixture of equal parts of peat moss and perlite or coarse sand will provide sufficient drainage to prevent waterlogging.
Pots and containers with blocked or absent holes at the base will prevent water from flowing out of the soil, even if the soil is well-drained and the plant is watered sparingly.
Ensure that you plant your peperomia in a container with drain holes in the bottom. Additionally, do not raise small plants in oversized pots, as these hold water for longer periods.
Some Peperomia species like the pilea love humid conditions; when the humidity is too low, the leaves start to curl. Air conditioners and heaters in the house make the air around the house drier, causing the leaves to curl.
You can increase the humidity around the plant by misting the leaves regularly or placing it in a humidity tray. Another solution is to get an indoor humidity monitor to manage humidity levels.
Light and Heat Stress
Peperomia plants prefer indirect light, in the presence of high-intensity light, the leaves will start curling. The light requirements of peperomia plants are best met by east or west-facing windows, as these will usually not receive the harshest sunlight that can damage plants.
Nutrient Deficiency and Toxicity
Potassium and Magnesium deficiency will make the bottom leaves of the Peperomia curl and turn yellow.
You can correct nutrient deficiencies with a balanced 10:10:10 liquid fertilizer, diluted to quarter strength, and applied monthly. However, only resort to fertilizer when other possible causes of curling have been ruled out.
Peperomia plants require little fertilizer and can quickly become overfertilized, leading to more problems, especially nitrogen and phosphorus toxicity, which can reduce the plants’ ability to absorb calcium.
Pests and Diseases
The destructive nature of some pests and diseases can manifest as curled leaves.
Fungus gnats are small black flies that like to lay eggs in the moist soils of potted plants. The flies’ larva feeds on the plant’s roots, thus causing the leaves to curl from dehydration.
Fungus gnat infestations are easily diagnosed as the insects fly about the plant and people. If gnats are present, you can use neem oil as an insecticide, spray the oil in the soil, stem, and leaves for at least seven days.
Mealybugs are insect pests that appear as white cotton-like masses on the underside of the leaves. These bugs feed on juices in the leaves. You can eliminate mealybugs with insecticidal soaps.
Healthy roots are white, hard to the touch, and long. Any roots that differ from this description are probably diseased and will cause the leaves to curl or turn yellow.
Root damage may be caused by overwatering, pests, and waterlogged soils.
Reasons Why Peperomia Leaves Are Drooping
Besides curling, peperomia leaves are prone to drooping, as well. Wilting or drooping is the loss of rigidity, where leaves hang lifelessly from the stems. It is brought on by diminished water levels in the leaves. When insufficient water is the problem, drooping is a coping mechanism the plant employs to conserve moisture by reducing its surface area.
Thus, under-watering causes leaves to droop. However, overwatering will also cause the leaves to droop as well, as too much water will kill the roots, cutting off the plant’s access to water.
When the drooping is not so extensive, you may salvage the plant by repotting it and trimming off wilted leaves and damaged roots. In severe cases, however, the plant might not recover even after repotting.
Improper watering is the primary cause of drooping leaves. However, other factors, like temperature and humidity, pest, and diseases, also make peperomia leaves droop.
Temperature and Humidity
Transpiration, the process where water escapes from the leaves of plants as vapor depends on temperature, humidity, and the type of plant.
In hotter temperature, the leaves will droop more often as the rate at which water leaves the plant increases. The same holds for low humidity because drier air absorbs moisture faster than moist air. In extreme cases, temperature and humidity may increase the rate of transpiration to a point where the plant loses water faster than it absorbs it. If not corrected swiftly, many of the leaves will droop, and the plant will eventually die.
Set the plant on a tray of pebbles filled with water, or use a humidifier to increase the moisture in the air around the plant, especially when central heating dries out the air. Additionally, position plants away from heat sources (like fireplaces) and intense sunlight.
Pest and Diseases
The larvae of fungus gnats feed on the roots of peperomia; severe infestations can damage the entire root system and render the plant incapable of absorbing water.
Overly moist conditions cause root rot, and the rot can spread to the entire root system if left unchecked.
Reasons Why Peperomia Leaves Are Falling
It can be alarming when leaves start falling off your Peperomia. Still, falling leaves are not always a cause for alarm, but instead are part of the plant’s life cycle, as the peperomia sheds older leaves to redirect energy to the newer leaves above.
However, if the fallen leaves are not old and from the lower parts of the plant, this is a sign of an underlying problem caused by factors like light, temperature, and fertilizer.
Light is essential for the proper development of any plant, as it plays a role in photosynthesis, the process where plants convert light energy to chemical energy. Generally, peperomia plants prefer indirect sunlight, but low light will result in a weakened plant as there is no energy source.
Additionally, the resulting lack of chemical energy retards the plant’s ability to utilize water, leaving the soil damp for too long and causing the roots to rot.
East and west-facing windows deliver adequate indirect light for plants. You can also augment lighting with a full spectrum grow light.
Peperomia plants are tropical and subtropical plants; as such, they do not enjoy the cold. The allowable minimum temperature for indoor plants is 50°F (10°C). Frequent exposure to temperatures lower than 50°F (10°C) will cause leaves to drop.
Too Much Fertilizer
Radiator plants do not require too much fertilizer, and excess fertilizer can cause the roots to burn from salts in the fertilizer. Burnt roots are incapable of supplying water to the plant. Accordingly, the leaves droop, turn yellow, and drop.
You can tell when a plant has been overfertilized if there is a crust of fertilizer on the soil surface. The solution to overfertilization is to flood the soil with water, allowing water to flow from the drain holes for several minutes. Better still, transfer the plant to fresh soil.
Peperomia Leaves Are Yellow
Usually, there’s nothing to worry about when you notice old leaves turning yellow and withering, although this might look unattractive. This problem is easily solved by pinching off the yellowed leaves.
Excessive yellowing, however, is a sign of an underlying problem. Yellow leaves are the result of excess sunlight, improper watering, or nutrient deficiencies.
Peperomia plants prefer indirect light and will grow well in such conditions. On the other hand, extended exposure to bright direct light causes the leaves to fade to yellow or have burnt patches at the tips and edges. Repositioning the plant will solve the problem of yellowing due to excessive sunlight.
Nitrogen deficiency is a common cause of yellowing leaves. The monthly application of diluted liquid fertilizer should take care of yellowing brought on by nutrient deficiencies.
Peperomia Plant Diseases
Radiator plants are susceptible to an array of diseases stemming from bacterial, fungal, and viral infections. These diseases affect the plants’ development, resulting in distorted leaves, stunted growth, and, in extreme cases, the plant’s death.
Some of the common diseases that afflict peperomias are discussed below, along with the methods of control.
Fungal diseases are caused by moist conditions, resulting from too much humidity and overwatering the soil.
Cercospora leaf spot is a disease characterized by brown or black raised spots on the undersides of leaves. Peperomia obtusifolia (baby rubber plant) is especially prone to this disease. To control this disease, spray the affected leaves with fungicides.
Another fungal disease is the Phyllosticta leaf spot, caused by a fungus called Phyllosticta spp. The disease is common in the watermelon Peperomia. The symptoms of Phyllosticta are leaf margins with round brown or black spots that gradually spread to the entire leaf.
Control Phyllosticta leaf spot disease by keeping the leaves as dry and possible and remove diseased leaves.
Root and stem rot is yet another fungal disease, where the plants start to rot at the soil level. A black lesion moving upwards to the leaves is noticed as the disease progresses. The roots of infected plants are black and soft. To control, treat new soil with fungi then repot the plant.
The Peperomia leaf spot virus causes ringspot disease. Symptoms of the ringspot disease are light or dark rings, distorted leaves, and stunted growth of the plant. After a while, the leaves start to die and fall off. There’s no control for this disease, so it is best to discard the plant.
The main pests of Peperomia are insects that double as vectors. As such, they attack plants and introduce disease-causing organisms. Examples of these pests are caterpillars, mealybugs, mites, fungus gnats, shore flies, and thrips.
Caterpillars are the larvae of butterflies; they are voracious eaters. Signs of a caterpillar infestation are quite clear as holes in the center of leaves or along the edges. The good thing about caterpillar infestation is they are usually over after a while as they change into pupae.
Mealybugs are the cotton-like materials you observe underneath the leaves and in the roots of the plant. Infested plants are usually stunted, and some parts of the plant begin to die in severe cases.
Mite infestations are usually unnoticed until the effects start to show. Initial symptoms are new leaves curled downwards, stunted leaves, and leaves with serrated edges.
The key to controlling mite infestation is covering the plant totally with pesticides.
Gnats are small black flies found around the soil or leaves. They can be confused with the shore flies, another pest of the Peperomia plant. The flies do not cause any damage to the plants, but their larvae do. The larvae look like worms with transparent bodies and blackheads; they spin webs on the soil surface similar to a spider’s.
Fungus gnat larvae feed on the root, root hair, and leaves close to the soil. This feeding allows disease-causing organisms access to the plants and causes damage.
To control fungus gnats, avoid overwatering and build of algae in the soil.
Shore flies are often confused with the fungus gnats, and like the gnats, the adult flies do not damage the plants. Instead, they feed on the algae in the soil and defecate on the leaves (small black or green spots), providing an entryway for diseases.
Insecticides are not very effective in controlling shore flies. As such, ensure you control the volume of water and the build of algae in the soil.
Thrips are tiny insects; adult thrips have hair on the edge of their wings. Their colors range from yellow to black, and they feed on the leaves of Peperomia plants, turning them distorted with scars. Thrips also infect ornamental plants with the tomato spotted wilt virus.
To control thrips, spray the leaves of your Peperomia plants and the soil with insecticides like neem oil for at least seven days.
Repotting Your Peperomia Plant
Repotting a radiator plant is often an effective way to rectify yellowing, drooping and falling leaves caused by root rot, fungus gnat larvae, or root rot. Repotting allows you to remove any damaged roots and transfer the plant into a pathogen and fertilizer free soil.
It is also recommended to repot peperomia plants after two or three years, as the potting soil will get compacted with time, increasing the chances of root rot as water does not flow easily through the soil.
As peperomias do not grow much, you can move the plant to a pot similar in size to the present one. The repotting process is as follows:
- Fill a new pot halfway with well-drained soil (equal parts peat moss and perlite or sand)
- Gently remove the plant from the container, and shake off any soil on the roots.
- You may hose down the roots if you have applied too much fertilizer to the plant.
- Use a sterile knife or scissors to cut off any damaged roots.
- Place the plant in the new pot and cover the exposed roots with the same (fresh) soil.
- Press gently on the soil to make it firm.
- Water the plant.
Watering, particularly over-watering, is the primary cause of most peperomia problems. As such, care should be taken when you water the plant.
Other problems that affect peperomia include pests and diseases, temperature, humidity, light intensity, and fertilizer application. Consequently, adjusting temperature, humidity, and fertilizer dosage can solve some peperomia problems.
Neem oil and insecticidal soaps can combat mealybug and fungus gnat infestations, while aggressive pruning of the affected leaves will stop diseases from spreading.
Lastly, transferring the peperomia to new soil and pot will give the plant a fresh start and a fighting chance.