Lawn Fertilizer Problems

Lawns, like any other tree or plant, require nutrients for healthy growth. Fertilizers, organic or synthetic, add nutrients to nutrient deprived soil to make it more fertile. Fertilizers contain the three primary nutrients nitrogen, phosphorus and potassium, as well as a variety of secondary nutrients and additives. Although the nutrients in fertilizer help grow lush, green lawns, there are a variety of problems associated with fertilizer misuse and improper application.

Fertilizer Burn

Does your lawn have brown patchy, localized segments that are anything but aesthetically pleasing? This is a common symptom of over fertilization and under fertilization. Synthetic fertilizers contain a variety of salts, which in large quantities, restricts the lawns ability to suck up water from the soil. This causes the appearance of tip burn, or localized, brown patchy areas. According to NASA, lawns that do not get enough potassium exhibit symptoms of tip burn around the tips and edges of the grass blades. Avoid over and under fertilization by testing your soil at university-based or private labs. The test results will determine how much fertilizer to apply, which greatly reduces the likelihood of misapplication.

Nitrogen

Fertilizers, depending on brand and application, contain different ratios of the three primary nutrients. The nutrient ratios, written on the front of fertilizer bags, are in the order of N-P-K (nitrogen, phosphors, potassium). Nitrogen helps plants with cell division and foliage growth, and in the case of lawns, lush green growth. However, according to NASA, too much nitrogen causes weak, but lush growth. The weakened, thin growth makes lawns susceptible to disease, and causes stress. Symptoms to look out for consist of initial, fast growing grass, and then weakened growth with patchy areas and discoloration. Keep in mind that different grass types and turf require different levels of nitrogen for healthy growth. Test the nutrient levels, at a university-based or private lab, in your lawn and remember that more is not always better when it comes to nitrogen levels.

Application

The proper application of fertilizer is vital for a healthy, green lawn. Organic fertilizers use compounds that must be broken down by soil microbes before nutrients are available for lawns. These slow acting fertilizers are great for continuous feeding, but do not produce instant results that many homeowners are accustomed too. Synthetic or chemical fertilizers are water-soluble; therefore, free moisture is required before application. Application of synthetic fertilizer should occur early in the spring months, and directly after a period of moderate rain. Avoid application before heavy rains, as the excess water can cause fertilizer runoff, which negates the benefits of the fertilizer and can cause environmental problems. Because all fertilizers vary for application, it is important to read the directions thoroughly before application to avoid the aforementioned pitfalls.

Sources:

http://soil.gsfc.nasa.gov/soilfert/npk.htm

Personal experience (garden supervisor for ACE Hardware)