Skip to Content

Thriving Yard is an affiliate for companies including Amazon Associates and earns a commission on qualifying purchases.

Why Are Your Dianthus Leaves Turning White?

Why Are Your Dianthus Leaves Turning White?

Share Or Save For Later

Willie Moore
Latest posts by Willie Moore (see all)

The Dianthus genus comes in more than 300 varieties, and one of its well-known variants is the Carnation flower (Dianthus caryophyllus) (source). Veteran and neophyte gardeners enjoy caring for the Dianthus, as it is easy to grow them from their seeds.

Dianthus leaves turn white because of diseases like chlorosis, fungal infection, and mottling. Other causes include an excess of soluble salts found in fertilizers and too much ethylene in the environment.

The rest of this article will explain why Dianthus leaves turn white and other factors to consider for proper Dianthus care. 

6 Reasons Why Dianthus Leaves Turn White

There are various Dianthus diseases, which include greasy blotches, wilting, and stem rots. Various pathogens cause these diseases, but appropriate plant management (e.g., fungicide use, indexed cuttings) can help.

Seeing your Dianthus leaves turn white is a cause for concern. Read on to learn why that happens and what you can do for each condition. 

Fusarium Bud Rot

If you’re seeing visible plump white mites and cottony white growth on your Dianthus plant, it may be because of a fungus called Pediculopsis graminum, which is carried by grass mites. The rot starts with buds but can ultimately infect leaves and other parts of the plant (source).

Eventually, the buds also decay inside. Once you see this condition, dispose of the infected parts immediately, control weeds in the growing area, and find a way to control the mites.

See 10 Reasons Why Your Dianthus Buds Are Empty

Carnation Mottle Virus

Mottle is a condition that makes your leaves very faint, and this is particularly common in Carnation cultivars. Improper handling and infected cutting knives can cause the spread of this virus (source).

Mottle can also cause faint yellow streaks (almost white), severe dwarfing, and deformation in carnation crops. To prevent the spread of the virus, disinfect your gardening tools regularly.

Carnation Ring Spots

The Carnation is also prone to its specific ring spot virus condition, with symptoms such as necrotic centers on the affected leaves, necrotic flecks, and veinal necrosis, giving the plant a white, sickly appearance (source).

Necrosis, the premature death of cells, can lead to yellowish, whitish, and wilted plant portions.

For proper virus spread control, sanitation is critical, especially during the plant propagation stages. Some use chemotherapy and thermotherapy to ensure virus-free plant stocks, especially for commercially-produced carnations.

Another good thing is that the Carnation ringspot virus is no longer as widespread as it used to be, though it was a significant economic disease for quite some time.

Excess of Soluble Salts

Using soluble salts in excess can cause plants to suffer from wilting, necrosis, marginal leaf burns, reduced growth, and overall vigor loss. This excess usually comes from the overabundance of this salt in fertilizers and other soil solutions (source).

To prevent this, check the proper calculation of fertilizer dilutions and ensure you don’t over-apply your fertilizer injectors.

Sensitivity to Ethylene

The Dianthus genus, particularly Carnations, are ethylene-sensitive. Exposure to ethylene leads to petal wilting, also known as “sleepiness.”

Prolonged exposure results in chlorotic and deformed leaves. As ethylene concentrations increase, white lines appear on a leaf’s edges for most plants (source).

Because ethylene is a natural hormone produced by plants, it can be difficult to control. It is often released in response to stress from rough handling and dehydration.

Although it might help to keep your Carnations separate from other plants that produce high concentrations of ethylene, fruiting plants in particular, the best way to prevent ethylene damage is to handle your plants gently and regularly disinfect your tools.

Severe Chlorosis

Lastly, chlorosis can cause the yellowing (and, in severe cases, whitening) of leaf tissues due to a lack of chlorophyll. Other causes include high alkalinity, damaged roots, and poor drainage.

The longer a plant goes through chlorosis, the more severe its symptoms.  Paling sometimes happens from a lighter green to yellow and white hues, indicating extreme conditions, sometimes even leading to total leaf death (source).

Avoiding and treating chlorosis will depend on what caused it, so it is best to check if soil treatment or foliar applications is the method.

How to Care for Your Dianthus

Given the many diseases that can happen to your Dianthus plant, you should prevent them by giving your plants proper care (source). Read on to know the ways you can care for your dianthus well.

  • Give them access to sunlight. Regardless of where you choose to plant your Dianthus plants, they need at least six hours of full sun each day.
  • Don’t overwater your plant. Water is essential for any plant, but take great care not to overdo it. Overwatering dianthus plants can attract root rot diseases and cause their foliage to turn yellow.
  • Make sure there’s enough air circulation. Dianthus need good air circulation, so take care not to have them mulched. Air circulation is particularly important around the stems. Plant Dianthus at least 12 to 18 inches (30–46 cm) apart. 
  • Use fertilizers. Despite the risk of too much soluble salts, it is still a must to use fertilizers. Dianthus plants thrive with all-purpose liquid fertilizers, which you can feed every six to eight weeks for continuous blooming.
  • Deadhead your plants occasionally. Removing dead or faded flowers from your plant is an essential part of caring for your Dianthus. It can encourage reblooming and gives you a chance to propagate them.
  • Constantly check for signs of disease. Start by checking the stem’s strength. If the flower’s head is more than 30° from the horizontal, there might be something wrong. Other signs include a sleepy appearance, discoloration, splits, blown heads, and slab sides. You can minimize these issues by alternating the heights of flower heads when planting them (source).


There are many diseases that can cause dianthus leaves to turn white.  Some of them are the fusarium bud rot, the Carnation mottle virus, and chlorosis. Fortunately, there are ways to address this through adequate care.

How you sanitize your tools, secure proper growth conditions, and handle treatment methods will go a long way to ensure the health of your Dianthus plants.

Recommended Reading: