Black Sooty Mold on Mexican Lime: Wash Off, Control Source

Wash off: Soapy water + rag, then hose shower
Find insects: Check undersides, stems, branch crotches
Systemic control: Imidacloprid soil drench (Bayer Advanced)
Improve air flow: Prune for circulation

Mexican lime has black powdery "fungus" on new growth within days. Neem oil, insecticide didn't work. Hasn't bloomed. Help!

It's Sooty Mold, Not Primary Fungus

Black coating = sooty mold on honeydew from sap-sucking insects (scale, aphids, whitefly). Neem doesn't wash it off—you must.

Insects recolonize rapidly. Systemic kills them at source. Once honeydew stops, mold weathers off naturally.

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