Hydrangea macrophylla Glowing Alps Sticky Leaves - Causes & Fixes

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Aphid Infestation

Aphids are small, soft-bodied insects that pierce the tender new growth of 'Glowing Alps' Hydrangea to suck out sap. As they feed, they excrete a sugary substance known as honeydew, which creates the characteristic sticky residue on leaf surfaces.

Very Common

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How to confirm: Inspect the undersides of new leaves and stem nodes for tiny, slow-moving green or black insects.

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1 Apply an organic insecticide spray to the plant to eliminate the aphid population and stop the production of honeydew.

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2 Gently wash the sticky residue off the leaves using a soft cloth or a gentle stream of water to prevent fungal growth.

3 Inspect the undersides of leaves and new growth regularly to catch any remaining pests before they multiply.

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Scale Insects

Scale insects attach themselves to the stems and leaf petioles of Hydrangeas, feeding on plant fluids. While they don't move much, their waste products result in a persistent sticky film across the foliage.

Common

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How to confirm: Look for small, stationary bumps or bumps that resemble scale armor on the stems or leaf stalks.

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1 Apply an organic insecticide spray to the foliage and stems to eliminate existing scale insects and their eggs.

Bonide Captain Jack's Neem Oil 32 oz

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2 Physically remove visible scale insects from stems and leaves using a soft cloth or cotton swab dipped in rubbing alcohol.

3 Wipe the sticky residue (honeydew) off the leaves with a damp cloth to prevent the growth of sooty mold.

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Whitefly Infestation

Whiteflies congregate on the undersides of Hydrangea leaves, sucking nutrients and secreting honeydew. This can lead to a sticky coating that often attracts secondary growth like Sooty Mold.

Common

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How to confirm: Gently shake a branch over a white surface to see if tiny white insects fly upward.

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shopping_cart Recommended Products

1 Apply an organic insecticide spray to the undersides of the leaves to eliminate adult whiteflies and larvae.

Bonide Captain Jack's Neem Oil 32 oz

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2 Use yellow sticky traps near the plant to capture flying adults and monitor the infestation level.

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3 Wipe the sticky leaves with a damp cloth to remove honeydew and prevent the development of sooty mold.

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Sooty Mold (Secondary Symptom)

While not the primary cause, Sooty Mold is a dark fungus that grows on the honeydew left by sap-sucking insects. The 'stickiness' may actually be the layer of fungal spores adhering to the residue.

Common

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How to confirm: Check if there is a black, velvety coating covering the sticky areas on the leaf surface.

build How to fix it

shopping_cart Recommended Products

1 Identify and treat the underlying sap-sucking insects (such as aphids, scale, or whiteflies) that are producing the sticky honeydew.

Bonide Captain Jack's Neem Oil 32 oz

0.9 L • 1 pcs • Organic

$10

In Stock

2 Gently wash the leaves with a soft cloth or a mild insecticidal soap to remove the dark sooty mold and sticky residue.