Weird patterns of growth in lawns are often the result of inaccurate applications of fertilizer. Streaking or burning is quite common when fertilizer is applied by hand or with spreaders that do not distribute the fertilizer evenly.
Spinner type spreaders in particular will throw blended fertilizers, having different particle sizes, at various distances. Most spreaders come with instructions or charts for calibration, but fertilizer formulations differ. Care should be taken to be sure you are applying fertilizers not only evenly but at the recommended rates.
It is good practice to apply only one-half of the fertilizer in one pass, then move over one-half the distance of the spreader width and apply the remaining recommended fertilizer. This will help avoid streaking and will allow an opportunity to readjust the spreader if needed to increase or decrease the rate. Fertilizers are corrosive, so it is important to thoroughly flush the spreader with plenty of water and dry it soon after use to prevent rust and corrosion.
The foliage of the turf should be dry when applying fertilizer to prevent wheel tracking from the spreader and potential leaf burn from fertilizer particles sticking to the leaves. Watering immediately after applying fertilizer will help dissolve the fertilizer particles and move the nutrients into the soil to the roots.
Published April 28, 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