Cleaning Sooty Mold from Homegrown Citrus: Safe, Effective Methods

What It Is

Black coating on oranges/grapefruit is sooty mold—fungi growing on honeydew excreted by sap-sucking insects (whiteflies, aphids, scale). The mold doesn't penetrate peel or affect flesh; it's purely cosmetic.

Cleaning Methods

1. Soap & water + soft brush: Removes surface mold. Your current method works but misses crevices.
2. Bleach dip (1:10 bleach:water): Submerge fruit 1 minute, rinse thoroughly. Bleach penetrates peel texture, killing embedded mold spores. No residue risk—peel is impermeable.
3. Commercial fruit wash: Surfactant-based; follow label.

Address the Source

Cleaning fruit is temporary. Control the insects:

• Inspect trees weekly for whiteflies, aphids, scale.
• Apply horticultural oil or neem oil at first sign.
• Encourage beneficials (lady beetles, lacewings) by avoiding broad-spectrum insecticides.

Sooty mold is harmless to eat. The bleach dip is the only method that reliably cleans deep peel crevices.