Have you noticed some white fuzz on your succulents lately? It may look harmless, but it could mean a pest infestation or a fungal disease. Succulents are known to be hardy plants but like most plants, they can be attacked by pests and diseases. Let us get to know what causes white spots on succulents and ways to treat them.
White fuzz on succulents: What are the most probable causes?
1. It could be due to mealybugs.
Mealybugs are common pests that tend to infest succulents. These tiny bugs usually thrive on indoor plants since they favor moderate temperatures. They look like a white cottony substance and they are found among the new growth on your succulents, usually at the base of the leaves or on the stem. They are hard to detect and shortly the leaves are already deformed and misshapen.
The probable causes for the presence of mealybugs include overwatering and excessive use of certain fertilizers. These pests spread quickly and it is ideal to eradicate them at the earliest signs to avoid any widespread damage. Not acting promptly may not just kill your succulent but the infestation may also spread to other plants.
These are the treatment options for mealybugs:
By using plant insecticides.
The use of plant insecticides is a common treatment option for pests. However, it is a good idea to settle for organic ones like neem oil. Chemical insecticides are effective but they can also harm beneficial bugs and some states restrict their use. If you choose to use them, make sure that the insecticide is compatible with your succulents as it may just inflict damage.
By using isopropyl alcohol.
Isopropyl alcohol is a cheaper option than insecticide but equally effective. Simply spray 70% isopropyl alcohol on the mealybugs and cover all angles to make sure that you are spraying all areas of the plants. The bugs die on contact and you will notice that the white substance will fade almost instantly. Wait for a few minutes once done and wash the dead mealybugs away with water.
Repeat the treatment process after a few days if you notice that there are still a few bugs. However, if you notice any burns on the leaves, opt for 50% rather than 70% of alcohol content.
By using ladybirds.
Ladybirds or ladybugs are natural predators of mealybugs and placing these bug warriors on your affected succulents is a big help. They are experts at hunting mealybugs and they will easily finish them off in no time at all.
How to prevent a mealybug infestation?
Here are some tips on how to prevent a mealybug infestation:
- Be sure to water your succulents moderately and do not overwater them.
- Inspect your plants regularly.
- Quarantine infected plants.
- Do not over-fertilize as it may create an ideal environment for pests instead of keeping your plants healthy.
2. It could be due to the epicuticular wax.
Some succulents may develop a white powdery film, some plants that were once vibrant become soft, pale and pastel-colored. This is all due to the development of epicuticular wax or Farina, an even dusting of powder. This thin layer of silvery film is often seen on plums, grapes and other plants.
To be sure if the white fuzz on succulents is epicuticular wax, try to examine the uniformity and if you notice an even coating it is probably farina. It is evenly distributed on the plant, but the thickness may vary depending on the species. The wax is a protective covering for plants and hydrophobic, making the water bead up to prevent too much moisture from entering the plants.
Farina helps the plants to stay moisturized and also serves as sunscreen to prevent plants from becoming sunburned. It also protects plants from pathogens, insects and other extreme conditions. Do not wipe off the wax from succulents as it has many benefits for them.
3. It could be due to powdery mildew.
The white fuzz on succulents may also be due to powdery mildew, a type of fungal disease. It is usually characterized by white powdery mold on the leaves. It is usually white but it could also become yellowish, brown or black-colored growths. This fungus grows in warm and dry places, which makes succulents more prone to it.
Powdery mildew does not spread on the entire plant and it is patchier compared to farina. It is fuzzy and tends to spread from one leaf to another. It does not look harmful at first but it is capable of taking away the nutrients of succulents until they wither. The leaves fall and succulents may even die.
This fungal disease is contagious and it is ideal to separate infected plants to avoid any further damage. Gently remove the infected leaves, and you could also use a fungicide to kill the fungus and stop the spread of infection.
4. It could be due to whiteflies.
These white, flying insects are usually found in leafy succulents. They multiply rapidly and the larvae are also white but the eggs are yellowish that turn brown when they are about to hatch. These insects do not produce evenly distributed powdery substances. They suck the nutrients and produce honeydew that causes mold growth.
Whiteflies usually stay under the leaves rather than on the surface and occupy hard to reach places. If your plants are infested, they become deformed and eventually wither if not treated promptly.
White fuzz on succulents could be indicative of several reasons. It could be due to a mealybug infestation in your succulents. It may also be due to epicuticular wax which has many benefits for plants or powdery mildew, a highly contagious fungal disease.
Image: istockphoto.com / Sabine Wagner