Banded streaks or irregular patterns in the lawn may be the result of uneven or excessive fertilizer application. Many lawn fertilizers contain readily available forms of nitrogen and the turf quickly responds to the fertilizer application. Areas where fertilizer was applied develop a rich green color and areas that were skipped, or where fertilizer was applied unevenly, remain lighter green or yellow in color. To remedy the situation, carefully apply fertilizer to the areas that were missed. Avoid reapplying fertilizer to areas that were already fertilized.
Fertilizer injury may occur if too much fertilizer is applied. Many fertilizers contain soluble salts, which can burn root tissues causing the lawn to turn brown if fertilizer is heavily applied. As a general practice, water the lawn thoroughly after fertilizing to wash fertilizer off the grass blades and into the soil. If excess fertilizer has been applied, soak the affected area with one-inch applications of water, three to four times, to help leach excess salts from the soil.
To avoid problems with fertilizer, measure your lawn to determine the square footage and calibrate spreaders or sprayers for uniform and accurate application of materials.