Kalanchoe Rosalina Don Bombero White Cottony Spots - Causes & Fixes

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

search Possible Causes

error

Mealybugs

These small, soft-bodied insects secrete a white, waxy, cotton-like substance to protect themselves. They feed on the sap of Kalanchoe succulents, often congregating in the crevices between leaves or near the base of the stems.

Very Common

lightbulb

How to confirm: Use a cotton swab dipped in rubbing alcohol to dab the white spots; if they dissolve and turn brown, it is likely mealybugs.

build How to fix it

shopping_cart Recommended Products

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

$10

In Stock

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

warning

Powdery Mildew

This fungal disease manifests as a white, dusty coating on the leaf surfaces, appearing more like flour than cotton. It thrives in high humidity and poor air circulation around the succulent's foliage.

Common

lightbulb

How to confirm: Check if the white spots can be rubbed off easily with your finger and look for signs of leaves turning yellow or curling.

build How to fix it

shopping_cart Recommended Products

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

0.9 L • 1 pcs • Organic

$12

In Stock

2 Improve air circulation around the plant and reduce humidity by avoiding overhead watering, which keeps the foliage dry.

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

Fiskars 5/8" Bypass Pruning Shears

Cutting Tools

$13

In Stock

warning

Cottony Blight (Sclerotinia)

While less common in succulents, certain fungal pathogens can produce white mycelium that looks like cotton. This usually accompanies stem rot if the Kalanchoe's substrate remains too damp.

Common

lightbulb

How to confirm: Inspect the base of the plant for any signs of mushy, dark, or decaying stem tissue accompanying the white growth.

build How to fix it

shopping_cart Recommended Products

1 Immediately remove and discard any stems or leaves showing white cottony growth to prevent the fungus from spreading to healthy tissue.

2 Apply a fungicide to the affected area and ensure the plant is in a well-draining medium to prevent further moisture-driven rot.

Bonide Captain Jack's Copper Fungicide 32 oz

0.9 L • 1 pcs • Organic

$12

In Stock

3 Repot the plant in a fresh, highly aerated substrate and use a moisture meter to ensure you only water when the soil is completely dry.