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Lophophora williamsii White Cottony Spots
eco White Cottony Spots

Lophophora williamsii – White Cottony Spots

Why does your Lophophora williamsii have white cottony spots? Diagnose the cause and fix it with our step-by-step guide.

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Jump to cause: Mealybugs Cottony Blister Scale Fungal Mycelium (Molds)

search Possible Causes

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Mealybugs

These small insects secrete a white, waxy, cotton-like substance to protect themselves while feeding on the sap of the cactus. In Lophophora, they often cluster in the crevices between the tubercles.

Very Common
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How to confirm: Use a magnifying glass or toothpick to see if the white spots move or can be scraped off easily from the plant surface.
build How to fix it
shopping_cart Recommended Products
1 Isolate the plant immediately to prevent the mealybugs from spreading to other succulents or cacti.
2 Treat the infestation by spraying the cactus with an organic insecticide to kill the insects and remove the waxy coating.
Bonide Captain Jack's Neem Oil 32 oz
Bonide Captain Jack's Neem Oil 32 oz
0.9 L • 1 pcs • Organic
$10
In Stock
3 Use a cotton swab dipped in isopropyl alcohol to manually remove any visible white cottony clusters from the crevices of the tubercles.
warning

Cottony Blister Scale

While less common than mealybugs, certain scale species produce a fluffy, white appearance that mimics cotton. They attach to the epidermis of the cactus and suck nutrients, leading to potential deformation.

Common
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How to confirm: Inspect the base of the tubercles for small, hard bumps underneath the white fuzz.
build How to fix it
shopping_cart Recommended Products
1 Treat the affected areas with an organic insecticide spray to eliminate the scale insects and prevent further nutrient depletion.
Bonide Captain Jack's Neem Oil 32 oz
Bonide Captain Jack's Neem Oil 32 oz
0.9 L • 1 pcs • Organic
$10
In Stock
2 Carefully remove visible white cottony clusters using a cotton swab dipped in isopropyl alcohol to stop the spread.
3 Ensure the cactus is in a well-draining environment to prevent the moisture buildup that scale pests prefer.
Legigo Perlite 20qt
Legigo Perlite 20qt
18.9 L • Perlite
$27
In Stock
warning

Fungal Mycelium (Molds)

If the cactus has experienced high humidity or poor drainage, saprophytic fungi can grow on the surface of decaying tissue. This presents as a white, fuzzy growth often accompanied by soft, mushy spots.

Common
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How to confirm: Press the area gently to check if the cactus tissue feels soft or hollow compared to healthy parts.
build How to fix it
shopping_cart Recommended Products
1 Remove any soft, mushy, or decaying tissue using sterilized tools to prevent the fungus from spreading to healthy parts of the cactus.
2 Apply an organic fungicide to the affected area to eliminate the fungal mycelium and protect the plant.
Bonide Captain Jack's Copper Fungicide 32 oz
Bonide Captain Jack's Copper Fungicide 32 oz
0.9 L • 1 pcs • Organic
$12
In Stock
3 Improve air circulation and drainage by repotting the cactus in a well-draining substrate containing perlite or clay pebbles to reduce surface moisture.
Legigo Perlite 20qt
Legigo Perlite 20qt
18.9 L • Perlite
$27
In Stock
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