Grass Stains on Carpets - Solution 1 How To Remove The Stain Vanish Preen for Carpets Grass stains on Carpets – Solution 1 Stain Solver Solution Vanish Preen for Carpets 1. Remove Dirt 2. Spray Vanish Preen for Carpets directly onto the stained area and leave the spray on between 1-5 minutes. 3. Blot the stain gently. 4. Heavy stains may require a second application. Didn't find the solution you were looking for? Stain Fabric Find a Solution Please Select A Stain And A Fabric Expert Tips Our top grass stain removal tip is to treat the stain promptly and while still fresh if possible. Old grass stains can also be combated using Vanish, but they may be more resistant than stains that are new and fresh. Take a clean, damp paper towel or cloth and remove as much excess moisture from the grass stained area. When you get the chance, buy Vanish and follow the instructions above to get rid of the stain.