How to Identify and Treat 9 Dracaena Diseases

The genus includes houseplant favorites like the snake plant, aka mother-in-law’s tongue (D. trifasciata), dragon tree (D. draco), corn plant (D. fragrans), and lucky bamboo (D. sanderiana).

Dracaena are known for their easygoing attitude, rarely facing problems with pests and diseases.

Note that I said rarely, not never.

Just because they are tough and adaptable doesn’t mean they are immune to disease. It goes without saying that keeping your dracaena healthy, in the right conditions, will make infection less likely. Diseases tend to strike specimens that are stressed by their environmental conditions.

In our guide to growing dracaena, we discuss how to cultivate these plants in your home.

If your dracaena isn’t doing too well, this guide can help you figure out what is causing the issue and how to solve it.

Here are the diseases we’ll cover:

Before we start looking at potential diseases, it’s worth noting that fluoride toxicity is common in Dracaena species, and the symptoms can look like it is infected with some sort of disease.

If your municipal water is treated with fluoride, it can accumulate in the leaves over time, preventing photosynthesis.

Symptoms generally start in the margins of the leaves, turning them brown and necrotic. Eventually, the entire leaf might even die.

To avoid fluoride toxicity, water with rainwater or filter fluoride out with charcoal or reverse osmosis.

Learn more about watering dracaena in our guide.

“Flecking” is another environmental issue to be aware of.

This problem causes white or cream spots to develop on the tips of the foliage and is most common on multicolored or variegated specimens.

It can be prevented by maintaining consistent moisture, light, and avoiding temperature fluctuations.

To start with, we’re going to look at a disease that is most common in outdoor specimens, but might affect houseplants now and then, as well.

1. Anthracnose

Anthracnose is a problem that can affect dozens of plant species, including those in the Dracaena genus.

The disease is caused by the fungus Colletotrichum dracaenophilum and, to a lesser degree, C. gloeosporioides.

Look for blackened or pinkish water-soaked lesions on the surface of the leaves. There might be rings of brown or black fungal growths inside the lesions.

These lesions can cover a majority of the leaf surface and may cause the foliage to become chlorotic and drop from the plant.

Remove any symptomatic leaves and spray with a fungicide.

Trichoderma harzianum or T. viride can be highly effective. Bacillus subtilis and B. pumilus are powerful options, as well.

2. Armillaria Root Rot

Another disease primarily affecting outdoor dracaena, armillaria root rot is caused by fungi in the genus Armillaria, usually A. mellea.

It attacks dozens of herbaceous and woody plants, as well as ferns and palms.

Once it’s present in the garden, it can rapidly spread from host to host. Fruit tree growers know just how awful oak root fungus, as it’s sometimes known, can be.

It can live in the soil and on plant debris for decades and can rear its ugly head seemingly out of nowhere when you introduce a new host, like an unsuspecting dracaena.

This particular disease just loves cool, wet weather with lots of water on the foliage.

As with some other diseases on this list, armillaria really only impacts outdoor specimens, though it could theoretically sneak indoors if the conditions were right.

Usually, you’ll see light brown or golden mushrooms at the base of the infected plant, but not always. You can also look for white fan-shaped mycelia just underneath the bark.

If you see the mycelia, it’s a pretty good bet that the roots are rotting under the soil. Occasionally, you’ll see dark spots or lesions on the leaves, and maybe some curling, but as with the mushrooms, these might not be present.

When the pathogen infects a host, the leaves will turn yellow, the stem will collapse, and the foliage will eventually die off. There’s no cure, so infected specimens will have to go.

Since this pathogen can infect both plants and humans, if you’re immunocompromised and you discover this problem on your houseplants, use extreme caution to bag up and dispose of the plant. Better yet, have someone else do it.

4. Black Stem

Black stem is a good description for this disease. As the name suggests, it results in black, rotting stems that can kill the dracaena.

It’s caused by the fungi Colletotrichum dracaenophilum, Corynespora cassiicola, and Thielaviopsis paradoxa, as well as some Fusarium species.

Read our guide to dracaena black stem to learn more about identifying and addressing this particular issue.

5. Fusarium Leaf Spot

Fusarium leaf spot is different from leaf spots caused by Phoma draconis, discussed below, and is sometimes just called fusarium disease.

It’s primarily caused by the fungus Fusarium moniliforme, but F. solani can also cause symptoms.

Symptoms generally appear on the younger leaves, and are usually water-soaked and dark, but as the lesions grow larger, they dry out and take on a reddish-brown or tan hue, with or without yellow haloes.

The spots can vary in size from as small as a pepper flake to an inch in diameter.

Fusarium can live in the soil for a decade or more and it’s pretty much impossible to get rid of. The best thing to do if you have an infected plant is to remove it and don’t grow anything in the area that is susceptible to fusarium.

If you catch the problem early, you can treat the plant and soil with a fungicide. If you’re growing your dracaena in a container, toss out the soil, rinse the roots off thoroughly, and pot in new soil.

6. Leaf Spot

Leaf spot is a generic term for any disease that causes spotting on the foliage.

Although in Dracaena species it’s caused by many different pathogens, Phoma draconis is the most common.

This fungal pathogen thrives in wet, humid conditions, so overwatering or excessive humidity can create the ideal environment for the fungi to thrive and reproduce.

When the fungus is present, the symptoms typically start on the lower, older leaves first.

Irregular, yellow spots develop and as the disease progresses, they turn brown and necrotic, and develop a purple margin.

In advanced cases, a yellow halo might develop around the lesions. Those necrotic areas will often have black spots, which are the fruiting bodies of the fungus, known as pycnidia.

Take care not to overwater and avoid watering on the foliage of the dracaena. If you’re keeping your plants in a humid area, consider increasing air movement by opening windows or keeping a fan running for part of the day.

The lower leaves will eventually collapse and fall off the plant. If you get in close, you’ll often catch a whiff of something foul and rotten smelling.

Water on the foliage, whether from a watering can or your sprinklers, contributes to the spread of this disease, as do hot temperatures.

The bacteria finds its way in through wounds or damaged areas, and once it does, there isn’t much you can do.

If the rot is in an area that you can safely prune away, go for it. The rest of the dracaena should be uninfected.

But if, as is most common, the rot is at the base of the dracaena, it can’t be saved. You’ll need to dig it up, bag it, and dispose of it in the trash.

8. Tomato Spotted Wilt Virus

You’re probably asking yourself why we’re talking about a disease that targets tomatoes, but TSWV targets thousands of garden plants.

It’s spread via thrips, so if you keep the pests away, you won’t have to deal with this virus.

Easier said than done.

If TSWV does infect your dracaena, you will see black or purple streaks on the stems. The plant might also be stunted and the foliage may drop off.

There’s no cure, so if you discover this problem, the only thing you can do is dispose of the dracaena.

9. Verticillium Wilt

Verticillium wilt attacks hundreds of plant species, dracaena included. It’s technically possible for this disease to impact a houseplant, but it’s rare. This is a problem you need to watch for in garden specimens.

The fungal disease, caused by the pathogen Verticillium dahliae, causes the plant to wilt and die. Typically, it will just be one branch or area that will die off first, sometimes it will just be one half of the plant that’s affected.

If your dracaena is wilting, in spite of sufficient water, or only certain sections of the specimen are looking droopy, remove a symptomatic branch and cut off some bark to expose the center of the wood.

If you see dark stains under the bark, you can be pretty sure it’s “vert” as this disease is often called.

So what do you do about it? Not much, once it has taken hold, since fungicides are ineffective against this pathogen.

Watering at the soil level and not on the leaves, cleaning your tools thoroughly between use, and ruthlessly pruning any other infected specimens can help to prevent the spread of this disease.

If your dracaena is only slightly symptomatic, prune off the wilting areas, and add a thick layer of mulch around the plant, but not touching the stem.

Mulch helps maintain consistent soil moisture and helps to fend off further infection.

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