White Cabbage Autumn Queen F1 White Cottony Spots - Causes & Fixes

Jump to cause: Powdery Mildew Mealybugs Sclerotinia (White Mold)

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Powdery Mildew

This fungal disease manifests as white, flour-like patches on the leaves of Brassica species. It thrives in high humidity and moderate temperatures, often spreading rapidly through a cabbage crop via airborne spores.

Very Common

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How to confirm: Look for white, dusty patches that can be wiped off with your finger but eventually cover the entire leaf surface.

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

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 airborne spread.

3 Improve air circulation around your cabbage plants and reduce humidity by avoiding overhead watering.

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Mealybugs

These small insects secrete a waxy, white, cottony substance to protect themselves and their eggs. On Autumn Queen cabbage, they often cluster around the base of the leaves or the stem, sucking sap and weakening the plant.

Common

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How to confirm: Inspect the undersides of leaves and the leaf axils for tiny, moving insects embedded in white fluff.

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

2 Apply an organic insecticide spray to the affected areas, ensuring you coat the base of the leaves and stems where the white waxy clusters reside.

Bonide Captain Jack's Neem Oil 32 oz

0.9 L • 1 pcs • Organic

$10

In Stock

3 Gently wipe away visible mealybug clusters using a cotton swab dipped in isopropyl alcohol to kill the insects on contact.

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Sclerotinia (White Mold)

This soil-borne fungus causes soft rot and is characterized by a dense, white cottony mycelium covering the plant tissue. It can cause the cabbage head or stems to decay rapidly in cool, damp conditions.

Common

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How to confirm: Check if the white spots are accompanied by mushy, decaying plant tissue and a distinct foul odor.

build How to fix it

shopping_cart Recommended Products

1 Immediately remove and destroy all infected plant tissue and surrounding debris to prevent the fungus from spreading through the soil.

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

Bonide Captain Jack's Copper Fungicide 32 oz

0.9 L • 1 pcs • Organic

$12

In Stock

3 Improve air circulation and reduce moisture by avoiding overhead watering and ensuring the soil is well-draining.