Why Do Dahlia Leaves Curl? (Answers You Need To Know)

Dahlias are a beautiful flower that can bring an incredible display of color and texture to any garden.

But when their leaves start to curl, it can be concerning.

What causes dahlia leaves to curl and is there anything you can do to prevent it? In this article, well answer these questions and more, providing you with the information you need to keep your dahlia plants looking their best.

Well discuss the causes of dahlia leaf curling, from dehydration to nutrient deficiencies, as well as how temperature stress can impact them.

Well also provide preventive measures and tips for the right amount of watering and fertilizing, as well as strategies for temperature regulation.

Read on to learn all about why do dahlia leaves curl and the answers you need to know.

Short Answer

Dahlia leaves curl due to a condition known as leaf cupping.

This is caused by a lack of water, a virus, or an abundance of fertilizer.

To remedy the issue, adjust the water and fertilization levels as needed.

If the leaves still curl, it is likely the result of a virus and the plant should be destroyed to prevent it from spreading.


Dahlia leaves can curl due to dehydration, which is caused by lack of water.

When the soil around the dahlia’s roots doesn’t contain enough moisture, the leaves will curl inwards in an attempt to conserve water.

Curled leaves are a sign that the plant is not receiving enough water.

If the dahlia is not regularly watered, it can become severely dehydrated and the leaves will eventually die.

To prevent dahlia leaves from curling due to dehydration, it is important to provide the plant with regular and adequate amounts of water.

The soil should be kept moist but not waterlogged, and the dahlia should be watered every few days, depending on the temperature and humidity levels.

Additionally, the plant should be watered from the base in order to avoid wetting the leaves, as this can encourage fungal diseases.

Nutrient Deficiencies

Nutrient deficiencies are one of the primary causes of dahlia leaves curling.

As with any plant, dahlias need a variety of essential nutrients in order to thrive.

If these nutrients are not provided in adequate quantities, the plant’s leaves can curl as a way of conserving energy and resources.

In particular, dahlias require adequate amounts of nitrogen, phosphorous, and potassium in order to remain healthy.

Nitrogen is essential for the growth of new foliage and provides a deep green color to the leaves.

Without sufficient nitrogen, dahlia leaves will become pale and may be more susceptible to curling.

Phosphorous helps to strengthen the plant and is important for root development and flower production.

Finally, potassium helps the plant to absorb water and nutrients from the soil and can also aid in disease prevention.

If you suspect that your dahlia plant is suffering from nutrient deficiencies, it is important to act quickly.

Start by testing the soil to determine what nutrients are lacking and then use a fertilizer that is specifically designed for dahlias in order to replenish the necessary nutrients.

Once the nutrient levels have been restored, the leaves should begin to uncurl.

Temperature Stress

Temperature stress is one of the most common causes of dahlia leaves curling.

When the temperature drops too low or rises too high, dahlia leaves can become stressed and curl up.

In general, dahlias prefer a moderate climate with temperatures between 60 to 80 degrees Fahrenheit.

Extreme temperatures can cause the leaves to curl in an attempt to conserve moisture and protect itself from the elements.

In addition to temperature stress, dahlias are susceptible to frost damage.

When temperatures drop below freezing, the leaves of dahlias can become brittle and dry, which can cause them to curl.

To prevent this, it is important to protect dahlias from frost and cold winds by covering them with blankets or plastic covers.

To prevent dahlia leaves from curling due to temperature stress, it is important to provide protection from extreme temperatures.

Make sure to cover dahlias with blankets or plastic covers in cold weather, and provide shade from excessive heat.

Additionally, be mindful of the location of the dahlia bed and choose a spot that is exposed to moderate temperatures.

With the right care, dahlia leaves will remain uncurled and vibrant.

Preventive Measures

When it comes to preventing dahlia leaves from curling, it is important to provide adequate moisture and nutrients, as well as proper temperature regulation.

Starting with moisture, dahlias need to be kept consistently moist, but not soggy.

Make sure to water them when the topsoil is dry, and supplement with a layer of mulch to help keep the soil moist.

Additionally, it is important to keep the leaves dry when watering, as wet leaves can lead to fungal diseases and curl the leaves.

When it comes to nutrients, dahlias are heavy feeders and need regular fertilizer applications.

Applying a balanced fertilizer every two weeks during the growing season will help ensure that they have enough nutrients to stay healthy and vibrant.

Additionally, soil tests can be done to check the nutrient levels of the soil and determine if any additional amendments are needed.

Finally, temperature is an important factor in keeping dahlia leaves healthy and uncurled.

Dahlias prefer temperatures between 60 and 70 degrees Fahrenheit, and should be protected from the cold.

In colder climates, make sure to mulch around the base of the plant to help insulate the roots and keep them warm.

Additionally, in areas with hot summers, providing some shade or supplemental water during the hottest parts of the day can be beneficial.

By following these guidelines, dahlias can stay healthy and their leaves will remain vibrant and uncurled.

With the right care, they will continue to be a beautiful addition to any landscape.


Watering is one of the most important factors in keeping dahlia leaves from curling.

Without enough water, dahlia leaves will become dehydrated, causing them to curl and become brittle.

In order to keep dahlia leaves from curling, it is important to provide adequate water.

How much water will depend on the climate, but it is generally recommended that dahlias be watered once a week.

If the weather has been particularly dry, more frequent watering may be necessary.

When watering dahlias, it is important to water deeply and thoroughly, as this will ensure that the roots are getting the necessary moisture.

Additionally, it is important to avoid wetting the foliage as this can lead to disease and other problems.

When watering, it is best to use a soaker hose or drip irrigation system to avoid splashing water on the leaves.


Fertilizing is an important step in preventing dahlia leaves from curling.

When selecting fertilizer, it is important to choose one that is specifically designed for dahlias and contains a balance of macronutrients.

These include nitrogen, phosphorus and potassium, which are essential for healthy growth.

It is also important to apply fertilizer according to the dahlia’s growth stage, as it can be damaging to the plant if applied too early or too late.

Applying fertilizer too late in the season may cause the leaves to curl and become discolored.

To ensure that the dahlia receives the right amount of fertilizer, it is best to follow the directions provided by the fertilizer manufacturer.

Additionally, it is important to monitor the plant for signs of nutrient deficiencies, such as yellowing or curling leaves, and to adjust fertilizer application accordingly.

Proper fertilization is key to keeping dahlia leaves healthy and uncurled.

Temperature Regulation

Temperature regulation is an important factor in preventing dahlia leaves from curling.

Dahlias are generally hardy plants, but they can become stressed when exposed to temperatures that are too extreme.

If the temperature falls below 50F (10C) or rises above 80F (27C), it can cause the dahlias leaves to curl.

This is because extreme temperatures can cause the plant to become dehydrated, which can lead to curling.

To keep your dahlias healthy and their leaves uncurled, it is important to maintain a consistent temperature.

During the summer months, keep the plants in a shaded area to prevent them from overheating.

In the winter, make sure the plants are well-insulated to keep them from becoming too cold.

In addition to temperature regulation, make sure your dahlias are protected from strong winds.

Wind can cause the plant to become dehydrated, which can lead to curling leaves.

If you are growing your dahlias in a windy area, be sure to take extra steps to protect the plants.

You can use burlap or other wind-blocking materials to help shield your dahlias from the wind.

Final Thoughts

Dahlia leaves curling can be an unfortunate sight, but with the right care, it can be prevented.

By understanding the causes of curling leaves, such as dehydration, nutrient deficiencies, and temperature stress, and taking the necessary steps to ensure adequate moisture, nutrients, and temperature regulation, dahlia leaves will remain healthy and uncurled.

With the knowledge you have gained from this article, you are now armed with the tools to keep your dahlia leaves looking beautiful!

James Simpson

James is a thirty-one year old man who loves to write about flowers. He is always eager to learn more about different types and how to care for them. He has a knack for finding rare and beautiful varieties and is always on the lookout for something new.

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