Kalanchoe Passion Castalia White Cottony Spots - Causes & Fixes

Jump to cause: Mealybugs Powdery Mildew Cottony Blight (Botrytis)

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Mealybugs

These small insects secrete a white, waxy, cotton-like substance to protect themselves as they feed on the sap of the Kalanchoe. They often cluster in the crevices between fleshy leaves and near the stem junctions.

Very Common

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How to confirm: Use a cotton swab dipped in rubbing alcohol to dab the spots; if the white substance dissolves and reveals small insects, it is mealybugs.

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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 to kill the insects and their waxy coating.

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3 Use a cotton swab dipped in isopropyl alcohol to manually remove visible white cottony clusters from leaf crevices and stem junctions.

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Powdery Mildew

This fungal pathogen manifests as a white, dusty coating on the leaf surfaces, often triggered by high humidity and poor air circulation around the thick Kalanchoe foliage. Unlike insects, this looks more like flour dusted on the leaves.

Common

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How to confirm: Check if the white spots can be easily wiped off with a finger and if the underlying leaf tissue appears yellowed or stunted.

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1 Apply an organic fungicide to the affected leaves to eliminate the powdery mildew spores and prevent further spread.

Bonide Captain Jack's Copper Fungicide 32 oz

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2 Improve air circulation around the foliage and reduce humidity by avoiding overhead watering and ensuring the plant is not crowded.

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

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Cottony Blight (Botrytis)

In high-moisture environments, Botrytis can cause gray/white fuzzy growth, especially on dying flower buds or decaying organic matter near the base of the plant. This is usually accompanied by soft, rotting tissue.

Common

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How to confirm: Inspect the base of the flowers and leaf nodes for any signs of mushy, dark brown tissue beneath the white fuzz.

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shopping_cart Recommended Products

1 Prune and remove all affected flower buds and decaying organic matter immediately to prevent the fungus from spreading to healthy tissue.

2 Apply an organic fungicide to treat the remaining healthy parts of the plant and protect against further infection.

Bonide Captain Jack's Copper Fungicide 32 oz

0.9 L • 1 pcs • Organic

$12

In Stock

3 Improve air circulation around the plant and reduce humidity by ensuring the soil surface dries out between waterings.