5 Most Common Reasons of Curling Tomato Leaves (And How to Fix Them)

Tomato leaves can curl for a number of reasons, including environmental stress, pests, and diseases. Here are some common causes of tomato leaf curling and what you can do about them:

Environmental stress

High temperatures, low humidity, and lack of sunlight can cause tomato leaves to curl. To prevent this, make sure your plants are getting enough water and sunlight and try to keep the temperature as consistent as possible.

Pests

Aphids, mites, and other pests can cause tomato leaves to curl. To get rid of these pests, you can try using an insecticide or a natural solution like neem oil.

Diseases

Certain diseases, such as tobacco mosaic virus, can cause tomato leaves to curl. To prevent diseases, practice good hygiene by keeping your garden clean and free of debris, and avoid planting tomatoes in the same spot every year.

How do you treat tomato leaf curl?

The treatment for tomato leaf curl depends on the underlying cause. Here are some general steps you can take to try and treat tomato leaf curl:

  1. Provide adequate water and sunlight: Tomato plants need plenty of water and sunlight to thrive. Make sure your plants are getting enough of both, and try to keep the temperature as consistent as possible to prevent stress.
  2. Control pests: If pests are causing the leaf curl, use an insecticide or a natural solution like neem oil to get rid of them.
  3. Practice good hygiene: To prevent diseases, keep your garden clean and free of debris, and avoid planting tomatoes in the same spot every year.
  4. Remove and destroy infected leaves: If the leaf curl is caused by a disease, remove and destroy any infected leaves to help prevent the disease from spreading.
  5. Apply a fungicide: If the leaf curl is caused by a fungal disease, you may need to apply a fungicide according to the manufacturer’s instructions.

If you’re unsure of what’s causing the leaf curling, it might be a good idea to bring a sample of the affected leaves to your local extension office or a plant specialist for identification and advice on how to treat the problem.

Does over-watering cause tomato leaves to curl?

Overwatering can cause tomato leaves to curl, as well as other problems like yellowing and wilting. When plants are overwatered, the roots can’t get enough oxygen and the plants can’t absorb water and nutrients properly. This can cause the leaves to wilt, yellow, and eventually curl.

On the other hand, underwatering can also cause tomato leaves to curl, as well as yellowing and wilting. It’s important to find a balance and water your tomato plants consistently, providing enough moisture to keep the soil evenly moist but not so much that the plants are standing in water.

How to fix it?

If you think your tomato plants are being overwatered, here are some steps you can take to try and fix the problem:

  1. Check the soil moisture level: Stick your finger about an inch into the soil near the base of the plant. If it feels moist, the plants are probably getting enough water. If it feels dry, it’s time to water.
  2. Adjust your watering schedule: Water your tomato plants consistently, providing enough moisture to keep the soil evenly moist but not so much that the plants are standing in water. A good rule of thumb is to water deeply once a week, or more often in hot, dry weather.
  3. Check the drainage: If the soil doesn’t drain well, the excess water can cause the plants to become overwatered. In this case, you may need to improve the drainage by adding compost or sand to the soil, or by choosing a different location for your plants.

Will too much fertilizer make tomato leaves curl?

Yes, too much fertilizer can cause tomato leaves to curl. When plants receive too much fertilizer, the excess nutrients can build up in the soil and cause the plants to absorb too much nitrogen. This can lead to a condition called “nitrogen toxicity,” which can cause the leaves to turn yellow and curl.

To prevent nitrogen toxicity, it’s important to follow the recommended application rates for fertilizers and to use a balanced fertilizer that contains a mix of nutrients (such as nitrogen, phosphorus, and potassium).

If you think your tomato plants may be suffering from nitrogen toxicity, you can try the following steps:

  1. Reduce the amount of fertilizer you’re using: Cut back on the amount of fertilizer you apply to your plants, or switch to a fertilizer with a lower nitrogen content.
  2. Flush the soil with water: This can help to leach excess nutrients out of the soil and reduce the risk of nitrogen toxicity.
  3. Apply a fertilizer with a higher phosphorus content: Phosphorus helps to balance out excess nitrogen and can help the plants recover from nitrogen toxicity.
  4. Remove and destroy infected leaves: If the leaf curl is caused by nitrogen toxicity, remove and destroy any infected leaves to help prevent the problem from spreading.

Should I remove curled tomato leaves?

It can be helpful to remove curled tomato leaves, especially if they are infected with a disease or infested with pests. Removing the affected leaves can help prevent the problem from spreading to the rest of the plant.

However, be careful not to remove too many leaves, as the leaves are an important source of energy for the plant. The plant needs its leaves to produce food through photosynthesis, so removing too many leaves can weaken the plant.

If you do decide to remove curled leaves, use clean, sharp scissors or pruning shears to cut the leaves off at the base of the stem. Dispose of the affected leaves in the trash, or burn them if the problem is severe.

It’s also a good idea to practice good hygiene in the garden to help prevent problems with pests and diseases. Keep the area clean and free of debris, and avoid planting tomatoes in the same spot every year. If you do see any pests or diseases on your plants, take action to treat the problem as soon as possible to prevent it from spreading.

Can tomatoes recover from leaf curl?

It’s possible for tomatoes to recover from leaf curl, depending on the underlying cause and how severe the problem is. If the leaf curl is caused by environmental stress, such as high temperatures or low humidity, the plants may recover on their own once the stress is relieved.

If the leaf curl is caused by pests or diseases, the plants may be able to recover if the problem is caught early and treated effectively. However, if the problem is severe or left untreated, it can weaken the plants and reduce their yield.

Will curled tomato leaves uncurl?

It’s possible for curled tomato leaves to uncurl, especially if the curling is caused by environmental stress, such as high temperatures or low humidity. Once the stress is relieved, the leaves may uncurl on their own.

However, if the leaf curl is caused by pests or diseases, the leaves may not uncurl on their own. In these cases, it’s important to identify and treat the underlying problem in order to help the plants recover.

If you’re unsure of what’s causing the leaf curling, it might be a good idea to bring a sample of the affected leaves to your local extension office or a plant specialist for identification and advice on how to treat the problem.