Bayer 704710B 2-in-1 Moss & Algae Killer Ready-to-Spray - 32 oz.
One formula kills Moss and Algae wherever it grows. Treats lawns, patios PLUS roofs and buildings. With other brands you'd need two formulas to treat all areas.  Kills: Moss, Algae, Lichen.  Where to Use: Lawns, decks, patios, fences, mulch, driveways, gravel, roofs and buildings. When to Use: Anytime during the year. Active Ingredients: Potassium soap of fatty acids: 22.11%.