Hello Gardeners, I’m Amanda McNulty with Clemson Extension and Making It Grow. It’s critical that you know what turf grass you have in your lawn. Cool season turf grasses begin active growth in fall and need fertilizer at that time. But warm season grasses are preparing for dormancy and should never be fertilized as fall approaches, not after August 15 give or take a week or so depending on your location. Although fall is an appropriate time to apply a pre-emergent herbicide for winter weeds, choose a brand completely free of the growth-stimulating element nitrogen. Sadly, I’m hearing advertisement for products aimed at winterizing southern lawns that contain high percentages of nitrogen and some of them also contain pre-emergent compounds. If you fertilize your lawn during the growing season, it does not need special fertilizers to prepare it for winter and there is no time of the year that you should ever apply a combination weed and feed product to your warm season turf grass.