Treatment #5 Is a winterizer for your lawn. Every lawn care company knows you need a winterizer…but just calling it that doesn’t make it so. After talking with the companies that treat lawns in the Manitowoc County (including so out of town companies from Green Bay, Appleton, Little Chute, etc.) here’s what I found: some have no idea what they are putting on (or will not tell the customer); some have only four steps and no winterizer; some said they applied whatever they have left laying around from round 3 and some put on the cheapest they could find from wholesalers, and very little, if any, slow release. At Storm… The Lawn Pro, we applied a heavy helping of a custom made premium winterizing fertilizer. this is a very important time released balanced treatment (24-0-20) with an emphasis on potash which supplies potassium for winter hardiness, disease resistance and general durability. This premium winterizing fertilizer is vital to the health and vigor of your lawn and not one other company will spend the extra money to do this.