It is always a pleasing sight to see daffodils, forsythia, flowering quince and other early spring flowering plants signal that winter has just about played its course and our landscapes and lawns will soon burst with new life. Often these first sights of spring stir us to get over anxious with lawn fertilization. Particularly since fertilizer granules provide a simple and easy carrier to distribute pre-emerge herbicides that must be applied to our lawns prior to weed seed germination if the herbicide is to be effective.
However, there is a downside to using many of these weed and feed fertilizers in the spring for our Southern lawns. Many of these fertilizers are formulated with high nitrogen contents for cool season turf species that can utilize the nitrogen at this time of the year. These fertilizes put on our dormant warm season turf species now will more than likely only feed winter weeds that will compete for space as our lawns begin their flush of spring growth.
With too early nitrogen fertilization you may also be setting your lawn up for cold injury from a late season freeze. Therefore, my suggestion is, if you use a weed and feed fertilizer as a carrier for your pre-emerge herbicide, try to find a fertilizer formulation that is low in nitrogen, or at least one that the nitrogen source is in a slow release form. Waiting until you have mowed the lawn at least twice before applying your spring nitrogen fertilization will provide more efficient use of the fertilizer and be better for the turf.
Published February 18, 2008
Dr. Wayne Wells is an Extension Professor and Turfgrass Specialist. His mailing address is Department of Plant and Soil Sciences, Mail Stop 9555, Mississippi State, MS 39762. wwells@ext.msstate.edu
