Lilium orientalis Cherbourg White Cottony Spots - Causes & Fixes

Jump to cause: Mealybug Infestation Botrytis Liliae (Lily Botrytis Blight) Powdery Mildew

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Mealybug Infestation

Mealybugs are small, soft-bodied insects that secrete a white, waxy, cottony substance to protect themselves. They congregate in the crevices of lily scales and leaf axils, sucking sap and causing stunting.

Very Common

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How to confirm: Use a magnifying glass to check if the white spots move or are attached to the stem nodes.

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

2 Apply an organic insecticide spray to the plant, ensuring you target the crevices and leaf axils where the white waxy substance is visible.

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3 Use a cotton swab dipped in isopropyl alcohol to manually remove any visible mealybug clusters from the plant scales.

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Botrytis Liliae (Lily Botrytis Blight)

This fungal pathogen thrives in high humidity and can manifest as grayish-white, fuzzy patches on lily petals or leaves. It often begins as small spots that quickly expand into a cottony mold mass.

Common

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How to confirm: Inspect if the white spots are accompanied by necrotic (brown/dead) tissue on the leaf edges.

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1 Prune and remove all infected petals and leaves immediately to prevent the fungal spores from spreading to healthy plant tissue.

2 Apply an organic fungicide to the affected areas to control the spread of the Botrytis blight.

Bonide Captain Jack's Copper Fungicide 32 oz

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

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Powdery Mildew

This fungal disease presents as a white, flour-like coating on the surface of the leaves. While more common in cucurbits, certain environmental stresses in Oriental lilies can trigger superficial powdery growth.

Common

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How to confirm: Rub the white spots with your finger to see if the powder easily wipes off the leaf surface.

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shopping_cart Recommended Products

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

Bonide Captain Jack's Copper Fungicide 32 oz

0.9 L • 1 pcs • Organic

$12

In Stock

2 Improve air circulation around the lily foliage and avoid overhead watering to keep the leaf surfaces dry.

3 Prune and dispose of any heavily infected leaves to reduce the fungal load in your garden environment.