Common Houseplant Diseases

Last Updated on March 15, 2022 by Admin

Like houseplant pests, diseases are another problem you will likely experience if you own indoor plants. But unlike pests, diseases are more preventable.

In fact, with proper care, you may never need to deal with them at all.

That said, it is a good idea to know the common houseplant diseases, how to identify, treat and get rid of them in case they occur.

In this article, I’ll go through the different diseases common to indoor plants.

Diseases

Besides pests, disease is another issue that your houseplants will face.

Disease is much harder to fix. Also, it’s more difficult to detect. Often, the symptoms appear when the damage has been done.

The good news is, they’re not as common as pests. And, if you take proper care of your plants, you’ll be able to reduce the risk of them getting sick.

Houseplant diseases come in many variations. Most of them will fall under one of these three categories, namely fungal, bacterial or viral.

That said, one of the most important things you should never forget to do when buying plants is to check it beforehand.

In addition to looking for pests and their symptoms, do look for health issues.

A healthy plant will look strong, healthy and bright in color. So, if you see discoloration, paleness, yellow leaves or soft stems or roots, don’t get it.

Use your nose as well. Smell the potting mix and give it a good touch. Like produce, it should smell fresh.

Don’t be afraid to get the plant out of its pot to examine the roots. If you look at the table below, a lot of the foliage issues stem from root health problems.

Fungi

Fungal disease is the number one disease to look out for when it comes to houseplants. Among them is powdery mildew which is a mold-like layer that can cover leaves.

Fungi spread via spores. As such, they can easily travel in the air with a gush of wind and land on your plants. Contact between plants or one of your plants coming into contact with fungi also infects it.

Like many microorganisms, fungi like cold, damp environments. This is why it’s not a good idea to leave standing water on your plant. Or, leave your leaves wet.

Watering in the morning also helps as it gives the water enough time to evaporate due to sunlight. In contrast, watering later in the day or during the evenings reduces the chance of evaporation because the sun goes down and the temperature starts to cool.

Fungus also spreads from one plant to another. So, a sick plant can easily infect the rest. This is why it’s important to examine your plants on a regular basis.

Symptoms of fungal infections include spots of different colors including gray, black or brown.

Once you see fungal growth, cut the damaged parts and apply a fungicide to stop it from spreading.

Bacteria

Bacteria is much smaller than fungi. So, you won’t be able to see it. In contrast, you can allow fungus to grow to examine in by cutting a leaf that’s infected and sealing it in a cold, dark place.

But, like fungi, bacteria also like damp conditions to grow.

Thus, too much water is once again a likely cause.

Like fungus, bacterial infections also present spots on leaves. So, if you’ve ruled out fungal disease, it’s time to use an antibacterial. But, do cut off the infected area first.

Viruses

Viral diseases are somewhat different from fungal and bacterial. While they’re similar damaging to plants, viruses can’t survive outside of cells.

They also can’t reproduce on their own.

This means that viruses are passed from one organism to another. It could be from your fingertips, the saps of other plants or insects.

Just as importantly, viral plant problems are hard to diagnose because their symptoms are very similar to other possible problems. And, the range of symptoms is also broader.

Additionally, each plant often will present varying symptoms.

Some will show slow growth. Others will have rings of different colors. And, yet others may have mottling.

Of course, there are instances where your plant may look healthy but it actually has a virus.

Unfortunately, there is no cure for plant viruses.

The good news is, they’re rare.

Related

Summary of the Common Diseases, Their Symptoms and Causes

Here’s a summary chart of the different signs you can look for to check for diseases in your houseplants.

On the left column, you have all the symptoms.
On the right column, you have what’s likely causing the symptoms. This will help you fix the problem.

chart of common houseplant diseases & their causes

You’ve probably noticed that most of the problems are caused by overwatering. In some cases, it may be dry soil dryness.

That’s the reason why watering too much is often what dooms houseplants.

Ways to Prevent Houseplant Diseases

Here are some useful tips you can use to prevent your beautiful indoor plants from wilting, losing color or dying from disease.

Make sure you use potting soil that’s sterile. Just using any kind of soil you pick up from the garden increases the risk of microorganisms.
Disinfect and sterilize old pots before putting new plants in them.
Clean your gardening tools. Blades or anything used to cut or prune your plants can introduce infection.
Don’t overwater your plants. Too much water that’s left standing opens the doors for pests and disease, not to mention root and crown rotting. Since water covers all the air pockets in the soil, it also deprives your plants of air which weakens them. This makes them susceptible to diseases.
Don’t wet the leaves. Leaving your plant’s foliage wet increases their risk of developing powdery mildew, which is a kind of fungi.
Make sure there’s enough circulating air.