Peace Lily Diseases: All You Need To Know

Peace lilies or Spathiphyllum are some of the most beautiful houseplants. As fragile as they may look on the outside, they are tough houseplants. Several hours of indirect sunlight, watering, well-drained soil, and occasional repotting are all you need to keep them blooming.

Since they are so easy to grow, peace lilies are the perfect houseplant to bring life to your room. Not only do they add to your room’s ambiance, but they also make it hospitable with their light scent.

However, sometimes these tropical houseplants can fall prey to diseases. If you have peace lilies growing at home, understanding the types of diseases that can affect them and their remedies is essential. In this guide, we walk you through those diseases and their ultimate solution.

Types of Peace Lily Diseases and Their Remedies

Before we discuss the various types of peace lily diseases, it’s important to know that they are not common. Usually, they pose a threat to commercial growers who produce peace lilies on a large scale for selling. You can simply prevent such issues by purchasing peace lily from a reputable nursery.

Also, don’t forget to inspect it properly before you bring it home. Choose healthy specimens, and avoid picking peace lilies with yellow leaves and wilting foliage.

Here are some peace lily diseases that can affect your houseplant along with their solution.

Cylindrocladium Root Rot

Cylindrocladium root rot is a fungal infection caused by overwatering peace lilies. It may also occur if the peace lily is planted in soil without proper drainage. Cylindrocladium root rot thrives in warm and humid conditions, where it can destroy the plant’s entire root system within a few months.

Unfortunately, Cylindrocladium root rot is difficult to diagnose, and your peace lily will only show symptoms after the disease has progressed for several weeks. The first sign of this fungal infection is the changing color of the plants’ leaves from green to yellow. In some cases, you may also experience wilting foliage.

If you look closely, you may also notice the appearance of dark brown spots on the plant’s leaves and petioles. But at this point, the chances of saving your peace lily are very grim, as it’s likely that its roots are rotten.

The best way to deal with Cylindrocladium root rot is through a fresh start. You’ll need to discard the infected plant along with the soil from the pot. If you wish to use the same pot for growing another peace lily, you should sterilize it first. This is because fungus produces infectious structures that might reside in the soil.

Dasheen Mosaic Virus

As the name suggests, the Dasheen Mosaic virus is a viral infection found in commercially grown peace lilies. Although it’s highly unlikely that this peace lily diseases infect your plant, the threat is always there. Dasheen mosaic virus gets its name from the mosaic patterns of yellow to light green that appear on the infected plant’s fresh leaves.

Dasheen mosaic virus is known to reduce or stunt the growth of your peace lily. In some cases, it has also proven to be life-threatening for the plant. Typically, this viral disease is transmitted through insects, such as aphids. It can also occur if you try to grow your peace lily in pre-infected potting soil and, sometimes, using infected gardening tools.

There is no known cure for the Dasheen Mosaic virus. Be mindful that this disease can infect other related houseplants, such as anthurium and philodendron.

Leaf Blight

Leaf blight is the most common among all other peace lily diseases. It is caused by Phytophthora nicotianae, a water mold that causes leaf blight on a wide range of plants. The main source of its transmission is splashing water, whereas moist and humid conditions make for an ideal climate for this disease to spread.

A peace lily infected by leaf blight will exhibit leaf margins and centers with black or dark brown spots. Under moist conditions, these spots may be wet and mushy; however, they may also be dry. As the disease progresses, these spots may expand into larger ones.

The best way to treat leaf blight is to repot your peace lily into a new, sterilized container. Keep in mind that this only works if you are lucky enough to spot the disease during its early stages. Always use fresh, sterile potting soil for this purpose.

Moreover, you should get rid of the affected foliage by cutting it and discarding it. Don’t forget to discard the old potting soil and sterilize the container thoroughly if you wish to use it again. You can also drench the soil by applying a fungicide instantly after repotting your peace lily. Remember that watering at the base of the plant while keeping the foliage dry is effective against this pathogen.

Pythium Root Rot

Pythium root rot is another peace lily diseases caused by a water mold, Pythium. This disease is very similar to Cylindrocladium root rot; the only difference is that the petioles aren’t infected in Pythium root rot. Therefore, it’s sometimes difficult to distinguish between the two diseases.

A peace lily diseases infected by Pythium root rot exhibits yellowish color and is often wilted. Unfortunately, by the time you discover the symptoms on the leaves, the roots will be black and mushy.

Remember that Pythium root rot prospers in damp, moist conditions. So, to prevent it from spreading, you should avoid overwatering. Plus, only try to water at the soil level and ensure that your plant has adequate drainage. Early-stage treatment of Pythium root rot requires repotting the peace lily and soil drench using a fungicide. In case your plant is severely affected, you are better off starting with a new plant.

Best Products for Soil Drenching

You now know of some infectious diseases that can be life-threatening for your peace lily. Under such circumstances, performing a soil drench can really help. But for that, you need to have the right products. One product we recommend checking out is:

Monterey Agri-Fos Disease Control Fungicide – The Most Effective Fungicide

[lasso ref=”monterey-agri-fos-disease-control-fungicide-pint-lg3340″ id=”4050″ link_id=”3364″]

It is also suitable for performing a soil drench.

Style: Liquid Spray

Application: Several ounces for full coverage

Size: 473 ml

Treatment Area: Foliage and garden use

Monterey Agri-Fos fungicide is also perfect for Phytophthora diseases. By just adding a few ounces with water, you can treat your plants infected by fungus. It comes in a large container so you can use it several times and is easy to use.


  • Convenient application
  • Large container for multiple uses
  • Optimal results against fungal infections


Peace lilies are the perfect houseplant to grow in your home. Although they are easy to grow, they can catch the visitor’s attention with their charming color and light fragrance. And while your peace lilies can lose their dazzle if they get infected, chances of that happening are extremely rare. Rest assured, by ensuring dry foliage, ample sunlight, and occasional watering, your peace lilies will definitely blossom.


What does fungus on a peace lily look like?

When a peace lily is infected by a fungal infection, the first symptoms are leaf margins and centers with either black or dark brown spots. Under moist conditions, these spots may appear to be wet and soggy. But, these spots can be dry if the shrubbery is dry.

How do I get rid of fungus on my peace lily?

There are numerous ways to treat a peace lily suffering from a fungal infection. One way to get rid of fungus is by spraying fungicide on its foliage. In cases of early treatment, you can consider repotting the plant with sterilized soil while getting rid of infected foliage. Don’t forget to avoid overwatering the plant or splashing soil and water on its leaves.

How do you fix an unhealthy peace lily?

If you want to fix an unhealthy peace lily, you need to ensure that it gets several hours of indirect sunlight. Keep it away from direct exposure to sunlight. You can also consider applying fertilizer once a month for its growth and nourishment. Plus, ensure a well-drained soil for the plant accompanied by slow watering to avoid splashes.

What does root rot look like on a peace lily?

If your peace lily is suffering from root rot, the foliage color will change from green to yellow. In addition, the leaves exhibit a wilting appearance. In case of severe infection, you’ll be able to see dark brown spots on the plant’s leaves.

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