The almighty, Patio Blast is a powerful cleaner for outdoor surfaces. It kills and controls green growth, algae, mould and lichens...including black spot and lasts for up to 9 months, meaning a clean patio all spring, summer and autumn long! Use on a multitude of surfaces including patios, walls, roof tiles, monuments, caravans, green houses, driveways, decking, conservatories, artificial grass, garden furniture and fence panels.