Updated: April 24, 2022

Dahlias are a popular garden plant known for their large and colorful blooms. However, like any other plant, they can suffer from various diseases and pests that can cause damage to the foliage. One common problem that gardeners encounter with dahlias is curled leaves. In this article, we will explore the different causes of dahlia plant leaves curling and what you can do to prevent and treat the issue.

Environmental Factors

Several environmental factors can cause dahlia leaves to curl. These include:

Lack of Water

Dahlias require regular watering to thrive. If they do not receive enough water, their leaves can start to curl and wilt as a result of dehydration. To prevent this, make sure your dahlias receive adequate water, especially during hot and dry weather.

High Temperatures

High temperatures can also cause dahlia leaves to curl. When exposed to heat, the plant may reduce its surface area to minimize water loss through transpiration, resulting in curled leaves. To prevent this, provide shade for your dahlias during hot weather or move them to a cooler area.

Low Humidity

Low humidity levels can cause dahlia leaves to curl and become crispy. To increase humidity levels around your dahlias, you can mist them regularly with water or place a humidifier nearby.

Pests

Several pests can infest dahlias and cause their leaves to curl. These include:

Aphids

Aphids are tiny insects that suck sap from the plant’s leaves, causing them to curl and become distorted. You can control aphids by spraying your dahlias with insecticidal soap or neem oil.

Spider Mites

Spider mites are another common pest that attacks dahlia plants. They feed on the plant’s sap, causing the leaves to curl and turn yellow. You can control spider mites by spraying your dahlias with insecticidal soap or neem oil.

Diseases

Several diseases can cause dahlia leaves to curl. These include:

Powdery Mildew

Powdery mildew is a fungal disease that causes white, powdery growth on the plant’s leaves. It can also cause the leaves to curl and become distorted. To prevent powdery mildew, make sure your dahlias receive adequate air circulation and avoid overhead watering.

Verticillium Wilt

Verticillium wilt is a fungal disease that causes the plant’s leaves to curl and turn yellow. It can also cause the stems to wilt and die back. Unfortunately, there is no cure for verticillium wilt, and infected plants should be removed and destroyed.

FAQ

Can I prevent dahlia leaves from curling?

Yes, you can prevent dahlia leaves from curling by providing adequate water, shade, and humidity levels for your plants.

How do I control pests on my dahlias?

You can control pests on your dahlias by spraying them with insecticidal soap or neem oil.

How do I prevent diseases on my dahlias?

You can prevent diseases on your dahlias by providing adequate air circulation, avoiding overhead watering, and removing infected plants promptly.

In conclusion, curled leaves are a common problem that many gardeners encounter with their dahlias. By identifying the underlying cause of the issue, you can take steps to prevent and treat the problem effectively. With proper care and attention, your dahlias will continue to thrive and provide colorful blooms for your garden.