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Pepper Plant Leaf Curl – 8 Causes & Practical Solutions

Pepper Plant Leaf Curl – 8 Causes & Practical Solutions

Growing pepper successfully requires extensive effort. While the plant is usually not picky, there are many possible challenges that may arise. Some of these difficulties may arise from insufficient care, while others are beyond your control. Leaf curl is a prevalent issue that can affect pepper plants.

When you notice your pepper plant leaves are curling, look for watering issues or inadequate temperature and humidity conditions.

It could also be a pest problem, poor lighting, diseases, plant edema, or not enough nutrients in the soil.

If the plant is growing in a pot, it might have outgrown the pot and the roots have no more space to grow.

Each one of those problems needs its own specific solution. Read on to find out how to tackle each issue and keep your pepper plant healthy. 

Causes of Leaf Curl in Pepper Plants

It’s not uncommon for the pepper plant to show signs of stress at the slightest change in the conditions around it. To monitor the progress of the plant, you’ll need to keep a close eye on the leaves. They usually reflect any signs of distress and start curling. When that happens, check for one or more of the following causes.

1. Watering Issues

The pepper plant can tolerate the occasional drought, but it can never survive in perpetually wet soil. If you overwater the plant, the sensitive roots will start to rot, which impacts the amount of nutrition that reaches the stems and leaves.

The leaves in turn will curl and shrivel as a result. Poor drainage often causes the soil to become waterlogged. Allow the top 1 to 2 inches of the soil to dry out before watering the plant again. 

2. Pest Issues

The main pests that attack the pepper plant are aphids, spider mites, and pepper hornworms. But it’s the cucumber beetle larvae that causes the most damage. As they feed on the roots of the plant, they cut down on the amount of moisture and nutrients the plant gets. That’s when the leaves curl and the stems wilt.

If not treated in time, the cucumber beetle larvae could prove lethal and cause the demise of the plant. Prevent the adult beetles from laying eggs near the roots by removing weeds and debris where the beetles might hide. Spray the other bugs with neem oil.

3. Temperature/Humidity Issues

Low temperature can prove fatal for the plant. On average, you should keep it cozy and warm in temperatures between 60 to 90 degrees Fahrenheit.

If the night temperature dips below 60 degrees F, the plant will struggle to grow and the leaves will curl. If it reaches 32 degrees F, the plant will die. 

4.  Disease

When the humidity levels are high around the plant, this opens the door to fungal infections. The most common fungal diseases are Fusarium wilt and Anthracnose.

They could also be spread by insects. So getting rid of bugs will prevent these diseases. Remove any infected plants to protect the other plants.

5. Lighting Issues

Poor light can cause many issues for the pepper plant. The plant expects plenty of sunlight at least 6 hours a day. If a larger plant casts a shadow on the pepper plant or filters the light, the leaves turn yellow and curl.

Ensure the plant is getting enough light and remove any obstacles near the plant that cut down the sunlight.

6. Nutrient Imbalance

Besides the usual nitrogen, potassium, and phosphorus which every plant needs, the pepper plant also needs calcium. It’s essential for the growth and overall health of the plant.

High acidity in the soil can lock the calcium and make it inaccessible to the roots of the pepper. Test the soil pH and make sure the pH levels are between 5.8 and 6.8.

7. Plant Edema

When the leaves of the pepper plants curl, check their underside. If it’s white, then the plant might have edema. It’s often caused by low humidity levels and poor airflow. Place a fan near the plant to improve ventilation.

If the air is too dry, mist the plant once or twice a week until the white texture disappears and the leaves flatten out again.

8. Potting Issues

Potting pepper plants can get root bound as the fast-growing plant develops a robust root system. This often happens when you start the plant in a small pot. To check for signs of root bound issues, check the drainage holes at the bottom of the plant.

If you see roots coming out of them, then you need to repot the plant and use a pot two sizes larger and add fresh soil.

Additional Common Pepper Plant Leaf Problems

In addition to the leaves of the pepper plant curling due to the above causes, the plant can also suffer from other issues. Here are the most common problems and how to remedy each one.

Yellow Leaves

Right before the leaves start to curl, they usually turn yellow. So in a way, you can consider the yellow leaves as a warning sign which you need to investigate. Too much water or too little water, poor light, lack of calcium in the soil, as well as fungal infections can all cause the leaves to turn yellow. Check for solutions to these problems above.

Black Leaves

Watering and overfeeding can cause the leaves to turn black. Too much water or poor drainage in the soil impact the roots, which in turn causes black leaves.

Allow the top one or two inches of the soil to dry out between irrigations. And when feeding the plant, dilute the fertilizer and use it at half strength. 

Leaves Turning Light Green

Lack of nitrogen in the soil can cause the leaves of the pepper plant to turn light green. Luckily, this problem is easy to fix by feeding the plant with a nitrogen-high fertilizer once every 2 weeks.

Switch back to a balanced fertilizer once the leaves regain their natural dark green color. Too much nitrogen can impact the flowering of the plant.

Wilting

Wilting can be the result of many changes in the conditions around the plant. It could be caused by poor light, using a strong fertilizer, overwatering, underwatering, poor nutrients in the soil, or diseases.

Both Fusarium wilt and Anthracnose can cause the plant to wilt and die if not treated properly.

Leaf Drop

This is a severe stage in a plant that’s been under stress for a long time. First, the leaves turn yellow, then they curl, and finally, they drop. The main culprit here is either too much or too little watering.

Make sure the topsoil is dry before you water the plant again. For potted plants, check that the drainage holes are not blocked by soil or roots.

Powdery Mildew

Powdery mildew is a fungal infection that appears in the form of white patches on the leaves. It’s spread by insects and both high humidity levels and poor air circulation can make the problem even worse.

Spray the plant with a mixture of baking soda and water and improve the airflow around the plant. You need to get rid of the infected leaves to prevent the spread of the infection to the rest of the plant.

Leaf Spots

In warm zones where the weather is often rainy and the humidity is high, leaf spots would appear on both sides of the pepper leaves. It’s a common bacterial infection that indicates that the plant is suffocating with the lack of airflow and high humidity.

As soon as you see the first spots, spray the plant with copper and Mancozeb sprays to kill the bacteria before it spreads to the other plants.

Mottled Appearance

The mottled appearance of the pepper plant leaves is often caused by the mosaic virus. It causes the leaves to have a bumpy surface and might even look deformed. Since this is a virus, there’s no treatment for the disease.

Your only option is to remove the infected plants. If the plants are mature, don’t keep any seeds from them. Dispose of all parts of the plants safely.

Pepper Plant Growing Tips

  • Always use a sunny spot for your pepper plants.
  • Make sure the soil pH is between 5.8 and 6.8 to avoid calcium locking.
  • Space the plants between 18 and 24 inches apart.
  • Add plenty of compost and organic materials to the soil before planting.

Related Questions:

How Do You Know If You Are Overwatering Pepper Plants?

Before watering the pepper plant, check the top one or two inches of the soil with your finger. If it’s dry, then you can water it. Overwatering often causes the leaves to turn yellow and curl as a result of root rot.

Can Peppers Recover From Overwatering?

It depends on how long the roots have been sitting in waterlogged soil. The damage to the roots is correlated to the amount of moisture in the soil. Inspect the roots and assess the damage. If most of the roots are rotting, you’ll need to start a new plant.

Conclusion

Pepper plant leaf curl is the result of overwatering, pests, diseases, poor light, or lack of calcium in the soil. Check the soil acidity levels to prevent calcium lock and make sure the plant is getting between 6 to 8 hours of direct sunlight every day.