Many grasses are heavy nutrient feeders and require regular application of fertilizer to replace the nutrients used. Applications of fertilizer are necessary during the growing season but also before the grass goes into dormancy during the winter months. Ohio State University claims that one of the most important times for lawn fertilization is the fall.
According to Penn State University the best time to apply fall fertilizer is after the foliage of the plant ceases to grow, or slows enough that the grass no longer needs a mowing. The grass must be green during the fertilizer application to prevent burning. Frozen soil will not allow fertilizer permeation so application must be done when the soil is still warm.
Late fall application maintains grass color throughout early winter. Fertilizer reduces the chance of disease and damage. Late fertilization also helps grass recover quicker in the spring and reduces the amount of fertilizer required to revitalize the turf. Fertilization increases root depth also.
Application amount is determined by the grass variety. Some turf grasses require more fertilization than others, so check with your local university extension for turf specifics. As a general rule, 1 lb. of nitrogen per 1,000 square feet of lawn for fast release fertilizer and 1 1/2 to 2 lbs. of fertilizer per 1,000 square feet of slow release fertilizer will do.
Virginia Gardening suggests testing the soil of your turf using your local university extension service before applying fertilizer to the lawn. Extra fertilization may be necessary if proper fertilization has not taken place. Virginia Gardening suggests a soil test every three years.
When applying fertilizer to the lawn, take care to keep fertilizer granules off the sidewalk and out of gutters. Fertilizer runoff may cause lake or groundwater contamination when blown away. Sweep up excess fertilizer immediately. Apply fertilizer using a drop spreader to keep the application tight. Run the spreader along the turf in two directions, crossing the previous application.