Psidium guajava White Cottony Spots - Causes & Fixes

error

Mealybugs

Mealybugs are small, soft-bodied insects that secrete a white, waxy, cottony substance to protect themselves. They attach to the stems and undersides of guava leaves, sucking sap and causing leaf yellowing or stunted growth.

Very Common

lightbulb

How to confirm: Inspect the leaf axils and stem junctions for tiny, moving white insects covered in fuzz.

build How to fix it

shopping_cart Recommended Products

1 Isolate the guava plant from other greenery and spray the affected areas thoroughly with an organic insecticide to kill existing mealybugs and larvae.

Bonide Captain Jack's Neem Oil 32 oz

0.9 L • 1 pcs • Organic

$10

In Stock

2 Manually remove visible white cottony clusters using a cotton swab dipped in isopropyl alcohol to prevent further sap depletion.

3 Monitor the plant's health and apply a preventative spray to protect new growth from re-infestation.

Bonide Captain Jack's Neem Oil 128 oz

3.8 L • 1 pcs • Organic

$35

In Stock

error

Cottony Scale

Similar to mealybugs, these scale insects produce a thick, white, felt-like coating on the guava fruit and branches. They excrete honeydew, which can lead to the growth of black sooty mold on the leaves.

Very Common

lightbulb

How to confirm: Look for a sticky residue (honeydew) on the leaves beneath the white cottony patches.

build How to fix it

shopping_cart Recommended Products

1 Apply an organic insecticide spray to the affected branches and fruit to eliminate the scale insects and their white coating.

Bonide Captain Jack's Neem Oil 32 oz

0.9 L • 1 pcs • Organic

$10

In Stock

2 Physically remove visible cottony clusters from the stems using a soft brush or cloth to reduce the pest population.

3 Clean the leaves with a gentle wash to remove honeydew residue and prevent the development of black sooty mold.

warning

Powdery Mildew

This fungal pathogen manifests as a white, dusty, or flour-like coating on the surface of guava leaves and young shoots. High humidity and poor air circulation around the guava canopy often trigger outbreaks.

Common

lightbulb

How to confirm: Check if the white spots can be easily rubbed off with your finger, leaving a clean leaf surface underneath.

build How to fix it

shopping_cart Recommended Products

1 Apply an organic fungicide to the affected leaves and new growth to eliminate the powdery mildew fungus.

Bonide Captain Jack's Copper Fungicide 32 oz

0.9 L • 1 pcs • Organic

$12

In Stock

2 Prune away heavily infected leaves and branches to prevent the spread of spores and improve airflow within the canopy.

Fiskars 5/8" Bypass Pruning Shears

Cutting Tools

$13

In Stock

3 Increase air circulation around the plant and avoid overhead watering to keep the foliage dry and reduce humidity.

warning

Woolly Aphids

These aphids produce fine, white, hair-like secretions that give them a cottony appearance on new guava growth. They congregate in dense clusters on tender terminal buds and young leaves.

Common

lightbulb

How to confirm: Examine the very tips of new guava shoots for dense, white, fuzzy clusters of small insects.

build How to fix it

shopping_cart Recommended Products

1 Apply an organic insecticide spray to the affected terminal buds and young leaves to eliminate the woolly aphid clusters.

Bonide Captain Jack's Neem Oil 32 oz

0.9 L • 1 pcs • Organic

$10

In Stock

2 Prune away the most heavily infested tender growth to prevent the aphids from spreading to healthy parts of the guava tree.

Fiskars 5/8" Bypass Pruning Shears