By Pat Dray
The Garden Spot
Pat Dray
Today’s gardening trend is to “rewild” a property instead of having large areas of turfgrass. Although I am all in on rewilding, lawns are part of suburban life so it’s helpful to understand when it does make sense to fertilize it to maintain its health. Since healthy turf is more disease and insect resistant, this one step may help reduce your overall use of herbicides and pesticides.
The very first thing you should do is to conduct a soil test to determine the specific nutrient needs and pH levels so that you prevent overfertilization or nutrient imbalances. Basic soil tests are available at no charge at the Connecticut Agriculture Experimental Station in New Haven or, for a more detailed test, through the University of Connecticut via their website soiltesting.cahnr.uconn.edu.
September is the time to apply the needed fertilizer. If your lawn is still actively growing, it can handle fertilizer. You don’t want to wait too late because grass should have time to absorb nutrients before it enters dormancy. Late fertilization can keep grass growing when it should be going dormant, increasing the risk of winter damage. Avoid applying just before heavy rain is expected to prevent any runoff.
By following these guidelines, fall fertilization can enhance root development, improve winter and ensure a lush, green lawn in the spring
Lawn maintenance fertilizers usually have grades like 32-0-4, 29- 0-4 or 10-0-6. These numbers refer to the percentage by weight of nitrogen, phosphorus and potassium. The higher amounts of nitrogen reflect the turfgrass’ greater need for it as it stimulates the production of new leaves and shoots above the soil surface. This new growth allows the grass to photosynthesize efficiently and generate energy for more sustained root development and disease resistance.
You may notice that the number for phosphorus is “0.” This is due to 2013 legislation in Connecticut that prohibits the addition of phosphorus fertilizers to established lawns except when recommended by a soil test performed within two years. Excess phosphorus in lakes fuels algal blooms, depletes oxygen and disrupts aquatic ecosystems, making it a major water quality concern. Phosphorus may be added when seeding or sodding a new lawn or when overseeding an existing lawn.
Potassium is used to help develop the root system. Except for deficiency situations, the amount of potassium found in maintenance fertilizers is sufficient for good turf growth. If additional phosphorus or potassium is needed, recommended grades and rates will be listed on your soil test results.
In keeping with the “less is more” approach to chemical use, remember that grass clippings add nutrients and organic matter to the soil. Contrary to popular belief, they do not contribute to thatch buildup. According to UConn’s Soil Nutrient Analysis Laboratory, turfgrass with clippings left in place needs about 50 percent less nitrogen fertilizer.