Hydrangea aspera Sticky Leaves - Causes & Fixes

error

Aphid Infestation

Aphids are small, soft-bodied insects that pierce the tender new growth of Hydrangea aspera to suck sap, excreting a sugary substance known as honeydew which creates the sticky residue.

Very Common

lightbulb

How to confirm: Inspect the undersides of young leaves and terminal buds for tiny green or black moving insects.

build How to fix it

shopping_cart Recommended Products

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

Bonide Captain Jack's Neem Oil 32 oz

0.9 L • 1 pcs • Organic

$10

In Stock

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 new growth regularly and use yellow sticky traps to monitor for any returning flying insects.

Super Ninja Fungus Gnat Traps - 30 Pack

30 pcs

$7

In Stock

error

Scale Insects

Scale insects attach themselves to the stems and leaf petioles of Hydrangeas, feeding on phloem sap and leaving behind a persistent sticky honeydew coating.

Very Common

lightbulb

How to confirm: Look for small, stationary bumps or waxy scales firmly attached to the stems that cannot be easily wiped off.

build How to fix it

shopping_cart Recommended Products

1 Apply an organic insecticide spray to the plant to kill existing scale insects and their eggs.

Bonide Captain Jack's Neem Oil 32 oz

0.9 L • 1 pcs • Organic

$10

In Stock

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 honeydew residue from the leaves with a damp cloth to prevent the growth of sooty mold.

warning

Whitefly Infestation

Whiteflies congregate on the undersides of Hydrangea aspera leaves; their feeding activity results in sticky honeydew and often a fine white powdery appearance.

Common

lightbulb

How to confirm: Gently shake a branch to see if a cloud of tiny white insects emerges from beneath the foliage.

build How to fix it

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

0.9 L • 1 pcs • Organic

$10

In Stock

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

Super Ninja Fungus Gnat Traps - 30 Pack

30 pcs

$7

In Stock

3 Wipe the leaves with a damp cloth to remove the sticky honeydew residue and prevent fungal growth.

warning

Sooty Mold (Secondary Condition)

While not the primary cause of stickiness, sooty mold is a black fungus that grows directly on the honeydew left by pests, eventually coating the rough leaves in a dark, crusty film.

Common

lightbulb

How to confirm: Check if the sticky residue is accompanied by a spreading black, velvety layer on the leaf surface.

build How to fix it

shopping_cart Recommended Products

1 Identify and treat the underlying pest infestation (such as aphids or scale) that is producing the sticky honeydew using an organic insecticide.

Bonide Captain Jack's Neem Oil 32 oz

0.9 L • 1 pcs • Organic

$10

In Stock

2 Gently wash the dark, crusty sooty mold off the leaves with a soft cloth and water to restore photosynthesis and leaf texture.

3 Monitor soil moisture levels to ensure the plant is not under environmental stress, which can make it more susceptible to pest attacks.