How to Get Erysiphaceae Off a House Roof
- 1). Mix 1 tsp. baking soda, 3 drops liquid detergent, and 1 qt. of warm water in the multipurpose spray bottle.
- 2). Shake the bottle vigorously until all ingredients are mixed in. The mixing might go better if you put the baking soda in the bottle first and then the water and the detergent.
- 3). Test spray the roof to make sure there are no adverse effects like discoloration. Wait one to three days for any adverse effects to appear.
- 4). Spray the roof if there are no adverse effects on all surfaces containing Erysiphaceae.
- 5). Repeat every seven to 14 days until the white powder disappears.
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