Why Should I Fertilize My Lawn in the Fall? Fall fertilizing is a crucial step in restoring your lawn to a healthy state. Fertilizing will help grass roots develop and strengthen so that your lawn will survive the winter. Winter Survival Fall Lawn Food contains humates, which aids in root development, is low in Nitrogen, providing a well balanced formula ideal for winter turf protection, and includes iron, to give the lawn a deep-green color. Looking for a quality, organic fertilizer?