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White Fungus and Fungus Gnats in Potted Lemon Tree

Fuzzy white in soil

Question: White powdery fungus on soil of indoor lemon tree, attracting gnats and larvae. Tree is healthy but fungus and gnats are unsightly. How to eliminate without harming plant?

Treatment

Fungus likely won't hurt plant, but fungus gnat larvae can. Drench soil with rotenone or pyrethrum if larvae are numerous. Fungicides labeled for containers exist, but simplest fix: cover soil surface with 1/2 inch pea gravel and forget about it.

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