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How to Get White Stuff Off of House Plants

House Plant - Croton image by evillager from

Houseplants that grow in environments with cool temperatures, inadequate air circulation and indirect sunlight may develop an unsightly fungal infection. Powdery mildew covers plant foliage with a white powder, often starting small and growing until it covers the leaves. Left untreated, powdery mildew can spread from plant to plant. Get the white stuff off houseplants and minimize damage to your plants by treating the powdery mildew before it damages your plants.

Move houseplants showing signs of powdery mildew to locations with more sunlight and air circulation and keep them away from other plants, if possible. While this will not reverse the powdery mildew, it should help minimize the spread of the fungal infection.

Clip all foliage with white mildew off the plant with the pruning shears. Make sure you remove every piece of foliage with powdery mildew with the pruning shears. Discard the foliage into the garbage immediately.

Wash your hands with antibacterial hand soap after handling the infected plant. Saturate a paper towel with isopropyl alcohol and use the paper towel to clean the blades of the pruning shears thoroughly. These precautions will minimize the possibility of spreading the powdery mildew between your infected and uninfected plants.

Spray the fungicide spray lightly, but thoroughly, over the remaining foliage and stems of the infected plant. Spray infected plants once per week with the fungicide spray to control the spread of the fungal infection.

White, Powdery Stuff On My Strawberry Plants?

Powdery mildew fungus infects the living tissue of wild or cultivated strawberry plants. Spores may be carried by wind to infect neighboring plants, so even if you plant disease-free seeds or transplants, it is possible for infection to occur after planting. When conditions are favorable, the white patches expand and merge until the entire underside of the leaves is covered. These are called cleistothecia and are white initially, but turn black as they mature. If the fungus infects older fruit, you may see fuzzy growth on the seeds. Sulfur-based fungicides are typically mixed at a rate of 1 to 3 tablespoons per 1 gallon of water, but each product varies in its ingredients and application so read the product label for specific instructions about application rate and timing. Repeat applications of sulfur fungicides in seven- to 10-day intervals as long as conditions favor development of infection to ensure new growth is protected.


Check the label of the fungicide spray before you use it on your plant to make sure it is suitable for your houseplant. Most fungicide sprays list the plants you can treat on their labels.

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