Crassula rogersii White Cottony Spots - Causes & Fixes

Jump to cause: Mealybugs Botrytis cinerea (Gray Mold) Powdery Mildew

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Mealybugs

These small, soft-bodied insects secrete a white, waxy, cotton-like substance to protect themselves. They congregate in the crevices of Crassula rogersii leaves and stems, sucking sap and weakening the plant.

Very Common

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How to confirm: Use a magnifying glass or smartphone zoom to check for tiny moving insects underneath the white patches.

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1 Isolate the plant immediately to prevent the mealybugs from spreading to your other houseplants.

2 Treat the infestation by spraying the plant with an organic insecticide or neem oil to kill the insects and remove the waxy coating.

Bonide Captain Jack's Neem Oil 32 oz

0.9 L • 1 pcs • Organic

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3 Use a cotton swab dipped in isopropyl alcohol to manually remove visible white cottony clusters from the crevices of the stems and leaves.

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Botrytis cinerea (Gray Mold)

In high humidity, this fungus can produce fuzzy white growth on succulent tissues. It often targets Crassula species when there is poor airflow or moisture trapped between the small leaves.

Common

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How to confirm: Check if the white spots are accompanied by soft, decaying, or mushy leaf tissue.

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1 Prune away all affected leaves and stems immediately using sterilized shears to prevent the fungus from spreading to healthy tissue.

Fiskars 5/8" Bypass Pruning Shears

Cutting Tools

$13

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2 Apply an organic fungicide spray to the plant to eliminate remaining fungal spores and protect new growth.

Bonide Captain Jack's Neem Oil 32 oz

0.9 L • 1 pcs • Organic

$10

In Stock

3 Improve air circulation around the plant and reduce humidity by ensuring the soil dries out between waterings, using a moisture meter to monitor levels.

GROWIT Soil Moisture Meter SMM-V3

Water Meters

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Powdery Mildew

This fungal disease manifests as a white powdery coating on the surface of the leaves. While more common in leafy greens, it can affect succulents under specific high-moisture conditions.

Common

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How to confirm: Observe if the white spots can be easily wiped off the leaf surface with your finger.

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shopping_cart Recommended Products

1 Treat the affected leaves immediately with an organic fungicide to stop the spread of the fungal spores.

Bonide Captain Jack's Neem Oil 32 oz

0.9 L • 1 pcs • Organic

$10

In Stock

2 Improve air circulation around the plant and reduce humidity to prevent the high-moisture conditions that favor powdery mildew.

3 Prune and discard any heavily infected leaves to prevent the fungus from spreading to healthy parts of the Crassula.