A Guide to Succulent Pests and Diseases

2. Spider Mites – Spider mites are very small and often go undetected for a long time since they are only 1/50 inch in length. The most common variety of spider mites is the red spider mites. The spider mites cause damage to succulents by sucking out the plant’s juices.

Symptoms – When the succulent is infested by spider mites they usually become lighter in color and may turn almost white or silvery. One of the first signs that you will notice is that there are webbing and small brown dots present in the affected plant.

Treatment – If you found out that your plant is infested you must immediately quarantine the plant so it will not affect the other plants in the garden. Spider mites can be removed from the plants by using a cotton swab dipped in rubbing alcohol.

You can also use dish soap diluted with water and use a spray bottle to apply the soap mixture to the affected plant. If the infestation is worse, repotting the plant must be done. Allow the plant to dry for a few days and repot them in a fresh potting mix that has well-draining soil, you can use this cactus/succulent mix.

Systemic pesticides can be used as a preventive measure. Pesticides can create a phototoxic reaction on the epidermis of the plants, so you have to take out the plants under the direct sunlight after the treatment for at least several weeks.

3. Scale – There are a lot of species of scale insects. The scale insects resemble small cottony shells and they are commonly found attached on the stems and leaves of the affected succulent plant. They can be scraped off using a toothbrush or high-pressure water spray. Scale insects suck on the plant juices of the succulent, causing it to become weak and have shriveled and wrinkled leaves.

Symptoms – When the succulent plant is affected with scale, you will see small brown bumps on the plant. Scale insects will attach to the plant tissue and if removed, it can cause a small scar on the plant. Scale insects can multiply quickly and affect other plants as well. This can give the plant a fuzzy appearance.

Scales usually prefer shade and avoid parts of the plant that are exposed in the sun. If a succulent has dense spination this will provide shade for the scale and they can spread to other parts of the plant that is not exposed to the sun. Scale insects are often found on plants that are new growth such as seedlings.

Treatment – Scale insects must be physically removed from the affected succulent plant. You can use a hose with a spray nozzle; just make sure the water is not strong enough to cause damage to the plant. For cactus plants, make sure to check the cracks and under the spines.

To prevent the repeated outbreaks of the scale, you must treat your plant with a systemic insecticide. The insecticide will be absorbed in the roots and into the plant tissue making the plant poisonous for the scale insect. The systemic insecticide must be applied during the growing stage of the plant and must be applied during the onset of the growing season. Make sure to physically remove the scale and wait for the insecticide to take effect.

Neem oil can also be used for treating scales. If the infestation is extreme, the neem oil may not be enough. You can use 15 ml of neem oil and mixed with 8 cups of water and mix it well. Spray the mixture on infested areas and the lower side of leaves. You can use the neem oil and apply it during the night to prevent the plant from getting exposed to too much sunlight. You can get the neem oil here.

4. Fungus Gnats – Fungus gnats are long black flies that look like mosquitoes. They measure 1/8 to 1/16 inch in length. They are commonly found above the soil surface. Larvae of fungus gnats live in the soil and consume the organic matter and roots of the succulent plant. Seedling succulent plants may have stunted growth or be killed because of the root damage that occurs during an infestation on fungus gnats.

Symptoms – If you water your succulent plants too much, the fungus gnats will become attracted and will start breeding. They prefer soil that is rich in moisture.

Treatment – You must only use well-draining soil and allow the soil to dry out in between watering. You can also use pots or containers like terracotta pots like this so it can drain the excess water accordingly. Use a succulent/cactus soil mix to prevent moist soil, you can get it here. You can also use pumice to help drain water and control excess moisture; you can get the pumice here.

You can also sprinkle cinnamon powder on the top of the soil, cinnamon is known for its natural anti-fungal properties. You can also use sticky insect pads and the fungus gnats will stick on the pads and help lessen the infestation problem.

5. Aphids – Aphids are tiny insects with bodies that look like teardrop shapes. They usually come in a variety of colors; the most common color is green. Aphids love to suck on leaves or flowers and as they feed they also excrete a sugary white substance. This white substance causes black mold growth on the affected succulent.

Symptoms – Aphids are often found in soft tissues of the plant and they suck on the plant’s juices. They are commonly found in the flowers and buds of the succulent plants. They prefer soft and new growth plants such as seedlings. As the aphids suck on the plant’s tissues, they also cause the plant to have stunted growth and misshaped leaves.

Treatment – You can get rid of Aphids by using a high-pressure water spray; make sure to do it several times to ensure that all the aphids are thoroughly removed. The water pressure must not be strong enough so you can avoid damaging the plants during the process.

If the problem persists, you can use a soapy mixture in a spray bottle and apply it to all affected areas of the succulent plant. If the infestation is worse, you can also use a systemic insecticide but you must only use it during the growing season of the plant so the plant tissues can absorb the chemicals.