Don’t fertilize lawns by signs of spring flowers (2-16-09)

Seeing early signs of spring with daffodils, crocus, tulips, and forsythia blooming greatly tempts us to work on our landscapes and bring out the fertilizer. Don’t rush into fertilizing your lawn too soon. This may be setting your lawn up for serious injury if we have a late freeze.

Heavy fertilization early in the spring when the lawn is just beginning to green-up will enhance foliar vegetative growth at the expense of cold tolerance, root development, deplete carbohydrate reserves and enhance diseases. You would be much better off delaying lawn fertilization until the turf has completely greened and temperatures have moderated more. A general guide is to wait until you have cut the lawn at least twice before applying spring fertilization.

If you just cannot stand not fertilizing, or if using a fertilizer carrier for the pre-emergence herbicide, then use a fertilizer low in readily available nitrogen. Several lawn fertilizers are characterized as slow-release formulations. These fertilizers contain water insoluble nitrogen (WIN) sources that are primarily not immediately available to the turf. The initial costs of these products are generally higher, but they perform much longer and reduce flushes of growth particularly when there is still danger of winterkill. Most lawns are still water saturated in early spring. Caution should be taken not to create compaction problems with heavy equipment such as riding lawn mowers, wheelbarrows, etc. once you do begin spring lawn chores.

Published February 16, 2009

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