Anthurium andraeanum Leganza White Cottony Spots - Causes & Fixes

Jump to cause: Mealybugs Powdery Mildew Spider Mites

search Possible Causes

error

Mealybugs

These small, soft-bodied insects secrete a white, waxy, cotton-like substance to protect themselves as they feed on the plant's sap. In Anthuriums, they often congregate at the base of the leaf petioles or in the junctions between leaves.

Very Common

lightbulb

How to confirm: Use a magnifying glass to check for tiny moving insects tucked into the leaf axils or under the foliage.

build How to fix it

shopping_cart Recommended Products

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

2 Use a cotton swab dipped in isopropyl alcohol to manually remove the visible white cottony masses from the leaf junctions and stems.

3 Apply an organic insecticide spray to the entire plant, ensuring you coat the undersides of leaves and crevices, to eliminate remaining insects and larvae.

Bonide Captain Jack's Neem Oil 32 oz

0.9 L • 1 pcs • Organic

$10

In Stock

warning

Powdery Mildew

This fungal disease manifests as white, flour-like patches on the surface of the leaves. It thrives in Anthurium environments with high humidity but poor air circulation.

Common

lightbulb

How to confirm: Observe if the white spots appear more like a surface coating that can be rubbed off rather than distinct clusters of insects.

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 by using a small fan or spacing it away from other foliage to reduce the humidity pockets that fungi thrive in.

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

Fiskars 5/8" Bypass Pruning Shears

Cutting Tools

$13

In Stock

warning

Spider Mites

While spider mite damage usually presents as stippling (tiny yellow dots), extreme infestations can result in fine, white silk webbing that looks like cottony residue across the leaf surface.

Common

lightbulb

How to confirm: Gently tap a leaf over a white piece of paper to see if tiny specks fall off and begin to move.

build How to fix it

shopping_cart Recommended Products

1 Apply an organic insecticide spray to eliminate existing spider mites and their eggs on the leaf surfaces.

Bonide Captain Jack's Neem Oil 32 oz

0.9 L • 1 pcs • Organic

$10

In Stock

2 Wipe the leaves with a damp cloth to physically remove the white webbing and any remaining mite residue.

3 Increase humidity around the plant, as spider mites thrive in dry environments, and monitor with a moisture meter to ensure consistent hydration.