Hydrangea macrophylla Magical Pink Cloud White Cottony Spots - Causes & Fixes

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

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Mealybugs

These small, soft-bodied insects secrete a white, waxy, cotton-like substance to protect themselves while feeding on the sap of your Hydrangea. They often cluster in the leaf axils or under the large leaves of 'Magical Pink Cloud'.

Very Common

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How to confirm: Use a magnifying glass to look for tiny moving insects at the base of the leaf stems.

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

2 Apply an organic insecticide spray to the affected areas, ensuring you spray under the leaves and into the leaf axils where the insects cluster.

Bonide Captain Jack's Neem Oil 32 oz

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3 Wipe away visible white cottony clusters using a cotton swab dipped in isopropyl alcohol to kill the insects on contact.

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Powdery Mildew (Early Stage)

While usually appearing as a fine dust, certain fungal infections can present as fuzzy, white patches on the foliage when humidity is high. This is particularly common in Hydrangeas during warm, damp periods.

Common

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How to confirm: Rub the white spot with your finger; if it wipes off easily like dust, it is likely fungal rather than insect-based.

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1 Apply an organic fungicide to the affected leaves to stop the spread of the fungal spores.

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 avoid overhead watering to reduce the humidity levels that promote mildew growth.

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

Fiskars 5/8" Bypass Pruning Shears

Cutting Tools

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Cottony Blight (Sclerotinia)

This fungal pathogen can cause white, mold-like growth on stems and leaves, eventually leading to stem decay. It thrives in the moist, shaded environments that 'Magical Pink Cloud' prefers.

Common

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How to confirm: Inspect the stem for dark lesions or soft, decaying tissue beneath the white patches.

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shopping_cart Recommended Products

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

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

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 overhead watering to ensure the foliage dries quickly, as moisture promotes Sclerotinia growth.