Succulent Diseases pictures (Ways to Prevent Succulent Diseases)

by Becky Decker and Anita Shan · August 5, 2024

Well, I am a succulent plant lover with a variety of succulents in my garden. Growing them has taught me about different succulent diseases and ways to prevent them.

If you’re considering growing succulent plants or already have some, it’s important to understand the main causes and diseases, as well as how to prevent them. In this article, I’ve detailed common succulent diseases so you can keep your plants healthy.

If you encounter any issues while reading the information, feel free to leave a comment in the comment section.

Table of Contents

Common Succulent Diseases:

While growing succulents pests and diseases is the major problem. The disease used to cause damage to the succulent plants. Although, many treatments are present for treating to help control the issues. The succulent plant gets infected with different types of insecticides, and fungicides, and where there are many natural remedies to treat them such as neem oil, diatomaceous earth, etc that are effective in managing pests and diseases in succulents. To treat succulent plants here I’ve explained common succulent diseases and different preventive ways for treating succulents:

Root Rot:

Root rot is a fungal disease mainly caused by overwatering or poor drainage that makes the succulent’s roots rot, leading to wilting, yellowing, and decay.

How to Treat Root Rot:

For treating succulents from root rot, just remove the plant from the soil and cut off all affected roots.
After cutting repot the plant in fresh, well-draining soil and make sure to reduce watering for preventing any further damage to the root.

Succulent Diseases pictures (Ways to Prevent Succulent Diseases)

Powdery Mildew:

The succulents do get infested with powdery mildew which is a fungal disease that does look white, powdery things on succulent leaves, stems, and flowers. They used to thrive in humid environments and spread more through the air so it’s important to maintain the growing environment dry and well-ventilated because the high humidity and stagnant air is perfect conditions making the powdery mildew develop. The plant getting infested with powdery mildew affects the plant’s ability to absorb sunlight, leading to stunted growth and diminished flowering.

How to Prevent Powdery Mildew:

You can prevent the powdery mildew from infesting, make sure to provide proper ventilation and avoid overwatering succulents.
In case you are growing succulents indoors, just use a dehumidifier to control humidity levels.

How to Get Rid of Powdery Mildew:

To get rid of powdery mildew, you can use a homemade solution of 1 part milk to 9 parts water directly by spraying it onto all affected areas.
You can also treat the succulents using a baking soda solution, neem oil, or a commercial fungicide.
Make sure to prune off all leaves, stems, or flowers having any signs of powdery mildew, and dispose of all the affected parts properly.
Just avoid composting the affected plant parts because the disease use to continue even after the succulent is dead.

Bacterial Soft Rot:

The bacterial soft rot is mainly caused by bacteria that used to thrive mostly in moist conditions and mostly happens when the succulent is overwatered or when they are growing in soil that does not drain well.

The main symptoms of bacterial soft rot are such as soft, mushy stems or leaves that get discolored with a foul odor. After reaching to advanced stage the tissue may turn black and appear waterlogged. The bacteria used to spread and affect the healthy tissue and when not treated on time the succulent may die.

How to Prevent Bacterial Soft Rot:

To prevent bacterial soft rot, firstly ensure the plant is not overwatered and is growing in the soil that is well draining.
Make sure to avoid watering on the leaves or stem of the succulent and always drain away any excess water.
You need to remove all affected parts of the succulent including leaves, stems, or roots, and just depose them.
Never reuse any infected plant material.

How to Treat Bacterial Soft Rot:

Make sure to treat all the remaining succulents using a bacterial solution such as a copper fungicide or a solution of hydrogen peroxide and water.
Remember to adjust the watering schedule according to the condition of the soil and improve drainage to prevent the disease from recurring.

Leaf Spot:

The succulent gets a leaf spot with a variety of fungi that used to thrive in moist environments and used to spread more in the wrong conditions. The main symptoms of succulent plants suffering from leaf softness include brown or black spots on the leaves that are circular or irregular in shape. The leaf spot may have a yellow or brown halo on it which results in leaves becoming distorted or wilted.

How to Treat Leaf Spot:

To treat the leaf spot on succulents with a fungicide and make sure to remove the infected leaves.
Using Copper-based fungicides is best for treating leaf spots which is easily available at most garden centers or online.
The leaf is soft to spread to multiple plants so firstly isolate the infected plant to prevent the disease from getting spread away.

Black Sooty Mold:

The Black sooty mold found on the leaves and stems of the succulent plants means the plant is affected by a fungus called sooty mold. The sooty mold is a type of fungus that appears as a black, powdery, or sticky substance on the leaves and stems leading to hindering their growth and will affect the appearance of the plant. All these symptoms make the succulent to suffer from an underlying issue.

How to Treat Black Sooty Mold:

The first step for treating succulents from black sooty mold is to isolate the affected plant to prevent the fungus from spreading to all other plants. This combination method will treat the mold and restore the plant’s health.
Make sure to remove all sooty mold parts physically by wiping them off with a soft cloth or brush that will remove the mold and improve the plant’s overall appearance.
Just make sure to wipe away the mold that is addressing the underlying cause of the mold.
To address the root cause, identify and address the underlying issue that leads to mold growth.

General Preventions and Treatments

Here the some main ways to prevent and treat succulent plants:

Neem Oil:

Neem oil is a natural oil that is derived from the seeds of the neem tree, native to India and other parts of South Asia. using neem oil is effective for treating and preventing a range of succulent pests and diseases such as aphids, spider mites, mealybugs, and scale insects.

The neem oil is used for controlling fungal diseases such as powdery mildew, black spots, and rust.

How Neem Oil Works:

Using neem oil disrupts the feeding and reproductive behavior of pests by inhibiting the growth and development of fungi.
Neem oil is safe to be used on plants that are approved for organic farming.
Remember, when overusing or misusing the neem oil will cause harm to beneficial insects and pollinators and will damage the succulent also.

Using neem oil to remove the farina from succulents:

Using neem oil does have unintended effects on the farina, which is a powdery white substance that covers some succulents such as Echeveria.
When you directly apply the farina it will cause the powdery coating to dissolve or become discolored resulting in losing succulent appearance.
To avoid spraying neem oil directly onto the leaves of the succulent pant having farina or try to use it by diluting it before applying.
In case of a pest infestation on a succulent with farina, you need to target the treatment such as insecticidal soap or rubbing alcohol on the affected areas not spraying the entire plant with neem oil.

Insecticidal Soap:

Talking about insecticidal soap is a type of pesticide, made from a solution of potassium salts of fatty acids. Using them will break down the protective coating on the surface of insects that is causing them to dehydrate and die.

Steps to make an Insecticidal Soap:

Take a potassium hydroxide that gets reacted with natural plant oils such as soybean oil which creates a soap-like substance.
The substance when diluted with water will create the final solution that you can apply in the plant with a spray bottle.
Using insecticidal soap is effective against the soft body insects and their eggs but less effective against hard-bodied insects such as scale insects and beetles.
Using insecticidal soap is safe for the plant because it’s low in toxic pesticides that break down in the environment.

Bifenthrin:

Bifenthrin is considered a synthetic pyrethroid insecticide which used to control a wide range of insect pests. You can use Bifenthrin in both agricultural and residential for controlling succulent pests.

How Bifenthrin Kills Pests:

Bifenthrin attacks the nervous system of succulent pests, causing them paralysis and death.
This means here the Bifenthrin comes into direct contact with the insect to be effective.
It is a long-lasting insecticide, which provides residual control for several weeks or even months when you apply it.
Bifenthrin is a formulation, including liquids, granules, and dust, which can be applied using different methods such as such as sprays, foggers, and baits.
Although it is considered relatively low in toxicity to humans and other mammals.
Using Bifenthrin is harmful to beneficial insects such as bees and aquatic organisms.

Imidacloprid:

It is a systemic insecticide that belongs to a class of chemicals called neonicotinoids which is a highly effective insecticide used for controlling a wide range of succulent pests.

How Imidacloprid Kill Pests:

Imidacloprid used to work with the nervous system of insects causing paralysis and death.
This is a systemic insecticide that absorbs the succulent and moves all over the tissues making the entire plant toxic to insects.
In the case of succulent pests having mealybugs, you need to feed the plant with imidacloprid where is get ingests the chemical and kills them.
Imidacloprid is found in varieties of formulations such as sprays, granules, and soil drenches, which you can use on a range of plants including succulents.
You can use it as a preventative measure for controlling succulent pests when they get infested but will control existing infestations.

Be Careful With Imidacloprid:

The imidacloprid is highly effective for controlling succulent pests and will not impact non-targeting organisms such as bees and other pollinators.
Make sure to follow the label instructions carefully while using imidacloprid and use it only when it’s necessary with all steps.
You need to store and dispose of the chemical property to avoid environmental contamination.
Let me share my experience of using imidacloprid, I use imidacloprid once or twice a season all over the garden to prevent any succulent pest infestations where I am careful while applying it when there are flowers present on the plant because I don’t want to kill any of the pollinators the flowers attract. In case of having active infestation, I spray imidacloprid on the whole plant and soil with a contact insecticide after which drench the soil with imidacloprid to get residual bugs leftover.

Diatomaceous Earth:

Diatomaceous earth is a substance that is made from the fossilized remains of diatoms and is considered a type of hard-shelled algae. The Diatomaceous earth is a powder that is composed of silica having abrasive and absorbent properties. During the process, the fossilized remains of diatoms are mined from deposits in the earth after which grounded into a fine powder which is used to treat in remove any impurities and for a variety of purposes such as pesticide.

Uses of Diatomaceous earth:

It is used to control a range fi succulent pests, including aphids, thrips, and spider mites.
When the insect comes into contact with the diatomaceous earth where the abrasive particle pierces their exoskeletons which results in dehydration and death.
They are effective at controlling slugs, snails, and soft-bodied succulent pests when they absorb the protective mucous layer that covers the bodies which leads to dehydration and death.
I use diatomaceous earth when ants are present in my succulents and I didn’t know where they’re coming from so I applied diatomaceous earth around the entire surface and anywhere where the ants might be hiding.
Make sure to use a food-grade diatomaceous earth because it will be safe for plants and animals in which follow the instructions carefully that help in avoiding inhaling the fine dust that result in irritating the lungs.

Isopropyl Alcohol:

Isopropyl alcohol is used as an insecticide for controlling succulent pests which dissolves the waxy protective coating on the insect’s exoskeleton resulting in dehydration and death.

How to use Isopropyl alcohol:

When you are using Isopropyl alcohol as a pesticide in which 70% isopropyl alcohol and 30% water are prepared you need to apply it to the affected plant using a spray bottle or a cotton swab.
Make sure to avoid getting the solution on the leaves or stem of the plant it causes chemical burns to the tissue.
The chemical burning affects the new growth in the middle in which it is possible not to see a chemical burn until the leaves start to grow out.
You need to rinse the succulents when treating it with alcohol.
Keep the plant out of the sun while the succulent is recovering.
Using Isopropyl alcohol is effective for succulent pests, including mealybugs, scale insects, and spider mites.
Isopropyl alcohol is harmful to beneficial insects such as ladybugs and lacewings so use it sparingly and only when it’s needed.
The Isopropyl alcohol solution is to be applied on a small area of the plant first to ensure it doesn’t cause damage or discoloration.
Don’t use Isopropyl alcohol on succulent plants which causes stress or weak the plant.

Beneficial Nematodes:

They are microscopic roundworms that are used as a biological control for managing a variety of succulent pests such as fungus gnats, thrips, and root mealybugs.

How to use beneficial Nematodes:

The beneficial nematodes actively seek out which infected insect larvae feed on them and resulting in killing them.
They use to reproduce within the insect host make it to release a new generation of nematodes into the soil, that continue to infect and kill insect larvae.
They are natural and environmentally friendly which manage insect pests in succulents that don’t harm beneficial insects, animals, or plants.
The Beneficial nematodes is effective at controlling pests that develop resistance to chemical insecticides.
Make sure to purchase high-quality Beneficial nematodes and apply them properly according to the method mentioned on the label.
Beneficial nematodes get mixed with water and applied to the soil by watering can or spraying bottle.
Make sure the soil is moist before applying to ensure that it can move through the soil, affecting the target insect pests.
The Beneficial nematodes are effective at managing succulent pests because it’s not as effective against all pest species.
Remember they are not effective against plant disease where it requires other management strategies.

Predatory Insects:

Talking about predatory insects which are beneficial insects that are used to feed on insects such as pest that damages succulents. Here consuming succulent pests the predatory insects get help to control their population and will reduce the cause to the plant.

The following are different types of predatory insects that are used for biological pest control:

Ladybugs: It is well known predate for aphids mealybugs, and other soft-bodied insects that when purchased and released onto the succulent will help in controlling the pest populations.

Lacewings: It is voracious predators of aphids, thrips, and other small insects when purchased and released onto the succulent will attract to the garden when you plant some different nectar-rich flowers.

Assassin bugs: It is the predatory insects that feed on insects including aphids, caterpillars, and thrips which get attracted to the garden when you plant flowers that have nectar and pollen.

Praying mantis: they feed on a variety of insects such as flies, aphids, and caterpillars which are released onto succulents which avoid releasing non-native species into the environment.

The predatory insects are natural and effective for managing succulent pests that are environment friendly which do leave behind harmful reassure that impact the health of the plant.
You need to carefully manage to ensure its effectiveness, in which make sure to purchase or attract the correct species of the pest to target.

Copper Fungicide:

It is a type of pesticide used for controlling fungal diseases in succulent plants where it releasing copper ions that are toxic to fungi and will inhibit growth and reproduction.

How to use copper fungicide:

You need to apply it on the foliage, stems, and roots of the plant to prevent or control fungal diseases such as root rot, leaf spots, and powdery mildew.
Using them is effective for bacterial diseases such as bacterial leaf spots.
They do have a variety of formulations having liquids, powders, and sprays.
Applying this will help to prevent the healthy plant risk of getting fungal infections or you can use them as curative treatment for controlling all the existing infections on the plant.
Make sure to follow the instructions on the label while using copper fungicides because it’s toxic to the plant when you use them in excessive amounts.
Overusing copper fungicides leads to the accumulation of copper in the soil which is harmful to all the beneficial microorganisms, and ecosystems.

Hydrogen Peroxide:

Using hydrogen peroxide is best for treating succulent pests and diseases due to its antifungal and antibacterial properties. After applying on the soil it helps in killing harmful microorganisms which result in root rot and other fungal diseases.

How to use hydrogen peroxide:

For using hydrogen peroxide for succulent pest and disease control mix it with water and apply it to the soil or spray the solution directly onto the plant.
It does result in strengthening the solution depending on the severity and type of plant.
It is the best solution for treating root rot in which one part hydrogen peroxide to three parts water is perfect.
You can apply the solution to the soil all around the affected plant but make sure to apply it on any leaves or stems of the plant.
The solution is used as a foliar spray to control fungal diseases such as powdery mildew.
The step for making foliar spray is to mix one tablespoon of hydrogen peroxide with one quart of water by spraying the solution on the leaves of the plant.
Be careful while using hydrogen peroxide on succulents which can be harmful in high concentrations.
You can dilute the solution as per the instructions mentioned and before applying test it on the small area to make sure it is not strong.

Conclusion:

Just make sure to follow the instructions mentioned above for treating succulents to avoid any damage to the plant. You can use beneficial nematodes and predatory insects as natural control measure that is the best defense against succulent pests and diseases by following basic requirements such as proper watering, sanitation, and choosing healthy plants. After you follow control measures the succulent will remain healthy and thrive for years.