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Tiny Black Flies in Houseplant Soil: Fungus Gnats from Overwatering

Shiny black flies = fungus gnats from soggy soil. No need to replace soil. Cut watering in half, never let tray hold water. Water once with rubbing alcohol, let sit 1 hour, then drain and let top 1–2 inches dry before next watering. Standing water rots roots and attracts gnats.

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