White Cabbage Compass F1 White Cottony Spots - Causes & Fixes

Jump to cause: Powdery Mildew Mealybug Infestation Sclerotinia (White Mold)

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Powdery Mildew

This fungal disease manifests as white, flour-like patches on the leaves of brassicas. It thrives in high humidity and moderate temperatures, eventually causing leaves to yellow and curl.

Very Common

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How to confirm: Inspect the underside of the leaves to see if the white spots are fuzzy or appear like dust that can be wiped away.

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1 Apply an organic fungicide to the affected leaves to eliminate the powdery mildew fungus and prevent further spread.

Bonide Captain Jack's Copper Fungicide 32 oz

0.9 L • 1 pcs • Organic

$12

In Stock

2 Prune and remove any heavily infected leaves immediately, ensuring you dispose of them away from your garden to prevent spore dispersal.

3 Improve air circulation around your cabbage plants and avoid overhead watering to reduce the humidity levels that favor fungal growth.

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Mealybug Infestation

Mealybugs are small insects that secrete a white, waxy, cottony substance to protect themselves. They suck sap from the cabbage leaves, leading to stunted growth and leaf yellowing.

Common

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How to confirm: Look for tiny, slow-moving insects nestled in the crevices of the leaf axils or near the base of the plant.

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shopping_cart Recommended Products

1 Isolate the cabbage plant immediately to prevent the mealybugs from spreading to other plants in your garden or greenhouse.

2 Apply an organic insecticide spray to the plant to eliminate existing insects and their eggs.

Bonide Captain Jack's Neem Oil 32 oz

0.9 L • 1 pcs • Organic

$10

In Stock

3 Carefully wipe off visible white cottony clusters from the leaves and stems using a cotton swab dipped in isopropyl alcohol.

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Sclerotinia (White Mold)

This soil-borne fungus produces white, cottony mycelium that can envelop cabbage leaves and stems. It often leads to rapid tissue decay and rot in high-moisture environments.

Common

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How to confirm: Check if the base of the stem is turning soft, mushy, or dark brown underneath the white fuzzy growth.

build How to fix it

shopping_cart Recommended Products

1 Remove and destroy all infected plant tissue and surrounding debris to prevent the fungus from spreading to healthy cabbage plants.

2 Apply an organic fungicide to control the spread of the white mold and protect remaining healthy foliage.

Bonide Captain Jack's Copper Fungicide 32 oz

0.9 L • 1 pcs • Organic

$12

In Stock

3 Reduce moisture levels by improving soil drainage and avoiding overhead watering, ensuring the soil surface stays dry.