A soil test will identify common nutrient deficiencies in your lawn, and can provide information on the proper amount of lime and fertilizer to apply. Soil testing is the only way to determine the proper ratio of nitrogen, phosphorus, and potassium to apply to a lawn. By applying only as much lime and fertilizer as is necessary and at the appropriate time, runoff into surface or ground water is minimized, money is saved, and plant health is optimized. However, a soil test is only as reliable as the sample you take.
The soil test results will provide liming rates and nutrient recommendations based on scientific research conducted in Delaware or in nearby states with similar soil types, climates and growing conditions.
The rates are designed to provide the nutrients needed to:
- help your lawn perform better
- maintain soil fertility in the range that is optimum for plant growth
- prevent the over-application of plant nutrients and lime, to avoid unnecessary costs and minimize any negative environmental effects on the quality of surface and ground water in Delaware.
When selecting fertilizer, you will find three numbers on the bag: the first number is the percentage of Nitrogen (N), the middle is Phosphorous (P), and the third is Potassium or Potash (K). Select a fertilizer that has no phosphorous unless your soil test recommends it. Because of the concern for excessive phosphorus in our waterways, many states are passing or have passed laws that restrict the application of phosphorus fertilizer. Select a fertilizer that contains 50% or more of the nitrogen in a slow-release form. Slow-release nitrogen lasts longer which provides a steady supply of nutrition throughout the growing season. This information can be found in the “Guaranteed Analysis” section on the back of the bag.