Use a garden sprayer to apply Lithofin MN Outdoor Cleaner generously in undiluted form. Allow the product to work for 2 to 10 hours depending on the stubbornness of the dirt deposits. Brush the surface and rinse with clear water. In very stubborn cases,repeat this procedure. Please Note: test the product's suitability in an inconspicuous area prior to use. Shield treated surfaces from rain for approx. 4 hours. Protect plants, textiles, metals, wood, etc. Product will damage these surfaces. Application Temperature: 10 to 22°C. Do not use on warm surfaces. Coverage: approx. 5 to 10m² per litre Hint: after several days, treat the surface with Lithofin ALGEX and repeat this treatment on a yearly basis. The preventive effect of Lithofin ALGEX will help to keep outdoor surfaces clean and free of green deposits.