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White Crust on Terra Cotta Pot: Mineral Salts, Not Mold

The white buildup on the bottom 3 inches of a terra cotta pot is mineral salts leaching from soil or hard water—not mold. Switch to filtered/distilled/rainwater if from hard water. Ensure pot isn't too large for the plant; oversized pots cause root rot. Email photo for size assessment.

House Plants: Gardenia Mealybug Infestation: Identification and Safe Control; Mold on Orchid Moss: Why Repotting Is the Solution; Powdery Mildew on Red Maple: Identification and Management; Powdery Mildew on Sarracenia: Sulfur Fungicide and Cultural Fixes; Drosera Filiformis Indoor Mold: Wrong Conditions for Dormant Species; Miniature Cyclamen in 2-Inch Pot: Water Often, Don't Repot Yet; Yucca's Natural White Film: Not Powdery Mildew; Maranta (Prayer Plant) Pot Size and Heat Tolerance; Powdery Mildew and Soil Mold on Indoor Plants; Mildew Smell in the Yard: Possible Sources and Steps

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