Top 5 Most Common Snake Plant Diseases (+ How to Cure)

Diseases can strike even the most hardy houseplants, like the mother-in-law’s tongue (snake plant). The most common diseases that snake plants are susceptible to are fungal diseases (compared to bacterial).

Fungal diseases in snake plants can vary considerably, affecting different parts of the plant, from the roots to the leaves. They can develop at different rates, and present themselves on your indoor plants in different forms. The most common diseases in snake plants are:

  • Root Rot,
  • Southern Blight,
  • Red Leaf Spot,
  • Rust, and
  • Powdery Mildew.
Snake Plant Disease

In this article, we’ll be taking a deep dive into each of these debilitating diseases that can have dire consequences for your snake plant if not treated promptly.

Common Snake Plant Diseases

Snake plants usually develop diseases when they are weak and cannot defend themselves. Each disease will have its own unique list of symptoms, and will attack different parts of a snake plant.

In fact, some diseases can be caused by common snake plant pests, as a result of the by-products the pests produce while they feed on the sap of the plant.

As we explore each disease, we’ll teach you how to keep an eye out for the symptoms. We’ll also detail a treatment program for you to implement to nurse your snake plant back to health.

1. Root Rot and Snake Plants

Root rot is by far, one of the most common diseases snake plant owners experience along the plant parent journey.

This is due to the fact that snake plants can easily become overwatered, leaving them with water-logged roots. The constantly moist environment encourages the development and growth of root rot, which spreads throughout the roots’ system. If left unchecked, the disease can work its way up into the leaves of your snake plant, causing the leaves to become wrinkled and mushy.

Unless root rot is transferred to the plants’ leaves through contamination (which is also very possible), the disease usually begins in wet soggy soil. Once it has manifested in the soil, it will infect the root system, eventually making its way up to the leaves.

Unfortunately, if the disease has reached the leaves, it generally means the entire root system is infected and the survival rate will be quite low for your snake plant.

How to Identify Root Rot?

Root rot is not the easiest disease to spot when it first infects a snake plant.

Because it usually starts in the soil, the first signs of the disease will be when the leaves begin to look sick, like turning yellow or falling over.

If you suspect your snake plant does have root rot, the best way to confirm your suspicions is to inspect the root ball.

Roots infected with root rot will be dark brown or black, mushy and smell rotten.

Advanced root rot will show at the base of the snake plant leaves. The leaves will be browning, appear and feel mushy, and also smell rotten.

snake plant root rot

How to Treat Root Rot

How you treat root rot will depend on how advanced the disease is in your snake plant.

If only part of the root ball is infected with root rot, your snake plant is still salvageable. If, however, the entire root system is infected, and the rot has begun to spread into the leaves, the only way forward is to propagate healthy parts of your plant.

For a step-by-step rundown of how to treat root rot, check out our Complete Guide to Treating Root Rot in Snake Plants.

2. Powdery Mildew and Snake Plants

Powdery mildew is a fungal based disease that affects the foliage of plants. When powdery mildew develops on snake plants, the leaves will appear to be covered with a matte white and black coating.

Like most fungal diseases, powdery mildew requires moisture to be present in order to thrive. It usually develops in periods when the ambient air is cooler and the plant doesn’t receive enough bright light to evaporate excess moisture that has collected on the leaves.

How to Spot Powdery Mildew

The easiest way to identify powdery mildew is to inspect the leaves of your snake plant. You will see a coating of white – gray powder on the surface of your leaves. If left untreated, spots may form on your leaves that appear like yellow/brown blemishes on your snake plant’s leaves.

snake plant disease powdery mildew

How to Treat Powdery Mildew in Snake Plants

Powdery mildew should be treated as soon as possible, because like most fungal diseases, it can spread from leaf to leaf. It can even begin to develop on neighboring indoor plants if the spores have an opportunity to spread through contact.

The quickest and best form of treatment is a simple fungicide that is applied to the infected leaves of the plant.

To prevent future infections, you may consider moving your snake plant to a brighter position that receives plenty of indirect light, and has sufficient air flow to assist with evaporation. Make sure you do not place your snake plant in direct sunlight, otherwise you may end up with leaf burn on your plant.

3. Southern Blight in Snake Plants

If your snake plant is showing symptoms of southern blight, you need to act swiftly. This fungal disease is no joke, and can become lethal for your snake plant very quickly.

This soil borne fungus (Schlerotium rolfsii) infects plants via the root system, and quickly makes its way up to the leaves of your snake plant. Fortunately, southern blight is not airborne; however like other fungal diseases, it can be spread by touch. So make sure you sterilize any equipment that has touched the disease with rubbing alcohol.

How to Identify Southern Blight in Snake Plants

The most common symptom of southern blight in snake plants are large brown spots that develop on infected areas of the leaves.

The brown patches will seemingly appear randomly on your snake plant, but it is important to act quickly and treat your snake plant for any potential signs of the disease.

How to Treat Southern Blight

Similar to root rot, we recommend a full repotting of your snake plant into fresh potting soil including a thorough treatment with a fungicide that is specifically manufactured to treat southern blight (contains azoles).

We also recommend removing infected leaves where possible.

For a complete guide to repotting your snake plant, refer to our step-by-step instructions in our GBT article.

4. Red Leaf Spot and Snake Plants

Snake plants can be prone to developing another fungal infection called red leaf spot.

Red leaf spot is caused by the fungus drechslera ersipila. The symptoms include reddish spots on the leaves. These spots usually start off small, but over time, they can spread across the entire leaf surface. Sometimes, the spots turn into dark brown blotches. In severe cases, the infected areas can even fall off.

How to Identify Red Leaf Spot on Snake Plants

As the name suggests, red leaf spot appears as reddish blisters on the surface of your snake plant’s leaves. There are often spots of liquid at the center of these blisters, and the surrounding flesh of the leaf may look like it is beginning to rot.

Snake Plant with red spots
credit: reddit

How to Treat Red Leaf Spot

The best way to prevent red leaf spot is to keep humidity levels at an appropriate level with sufficient air circulation. If you live in a particularly dry climate, try positioning your snake plant on a DIY humidity tray.

You can also use fungicides to help control the problem. For example, try spraying the plants with Bordeaux mix every three weeks for about five minutes. Follow up with a spray of tea tree oil.

5. Rust in Snake Plants

Rust is another fungal disease that affects the leaves of your snake plant.

It usually infects older, more mature snake plants or weakened plants that may be suffering from other issues like water stress, incorrect humidity or lighting conditions.

Like root rot, rust is more likely to develop in moist environments, and can be transferred to healthy plants with the spread of the spores.

How to Identify Rust on Snake Plants

Rust is as it sounds, looks like rust like blemishes on your snake plant’s leaves. It will begin to show as white to yellow spots and progress to show as brownish-reddish stains on the leaves.

The blotches are often accompanied by reddish blisters on the underside of the leaves. These blisters can sometimes have red liquid pustules where the sap from the snake plant leaves is oozing out.

Rust Treatment for Snake Plants

Removal of infected leaves is the best form of prevention for limiting the spread of the disease. Once you have cut away any diseased leaves, treat the remainder of the plant with a fungicide to ensure there is no future outbreaks of the disease.

Common Snake Plant Diseases – Final Words

Even though snake plants are easy to care for indoor plants, they can still be infected by fungal diseases if proper husbandry care is not provided.

Fungal diseases like root rot and rust flourish in moist, wet environments, like overwatered snake plants. Diseases will also often attack plants that are already in a weakened state, and are not able to fight off any diseases.

The best form of prevention is to provide the care and attention your snake plant deserves.