Moss Graffiti In your blender, combine: One can of cheap beer or 1 1/2 cups buttermilk A few handfuls of moss One teaspoon of sugar. Blend until the mixture is smooth, and you're ready to get painting! You can use a brush to paint your moss onto concrete walls, rocks or brick. Mist the moss once a day to help it thrive, and soon your green graffiti will take hold! On the side of the house over the herb garden...this i can do!