by Connie Oswald Stofko
Most lawns don’t need phosphorus. And if you use a fertilizer containing phosphorus on your lawn, the excess phosphorus can wash off and pollute our waterways.
That’s why the New York State Department of Environmental Conservation is running its “Look for the Zero” campaign. If you want to use a chemical fertilizer on your lawn, make sure you choose one without phosphorus.
Fertilizer labels have three numbers. The number in the middle is the percentage of phosphorus in the product, such as: 22-0-15. Look for that zero in the middle.
New York’s nutrient runoff law
New York’s nutrient runoff law prohibits the use of phosphorus fertilizers on lawns, with two exceptions:
- If a new lawn is being established.
- If a soil test shows that the lawn does not have enough phosphorus. Don’t guess; you actually have to test. See more about soil testing in this article. You can see an order form for soil testing here— On the form, choose “(856) Home Lawn.”
According to the law, you can apply fertilizer to a lawn only from April 1 through the end of November.
The law requires retailers to post signs notifying customers of the terms of the law and to display phosphorus fertilizer separately from phosphorus-free fertilizer. DEC is encouraging consumers to review bag labels for phosphorus content when shopping for fertilizer.
New York’s nutrient runoff law doesn’t affect agricultural fertilizer or fertilizer for gardens; you can use fertilizers with phosphorus on gardens.
Gardeners can help our waterways
Excess phosphorous from lawns can wash off and pollute lakes and streams, making them unusable for swimming, fishing, or as a source of drinking water. Towns often have to close beaches or boating areas. More than 100 water bodies in New York State cannot be used or enjoyed due to phosphorus overuse, according to the DEC.
“The actions New Yorkers take in their backyards can have a big impact on the environment,” said Commissioner Basil Seggos. “By choosing sustainable lawn care homeowners are helping to protect water quality and public health.”
For more information, visit DEC’s Lawn Fertilizer web page.
Alternatives to chemical fertilizer
You don’t have to use chemical fertilizers, according to the DEC. Organic lawn care can easily be implemented on any lawn. Safe and effective alternatives exist for most chemical pesticides and fertilizers. Visit DEC’s Sustainable Landscaping web page to learn more.
Additional recommendations for sustainable lawn care include spreading a quarter inch of compost on the lawn to improve moisture retention and soil texture and to add beneficial microorganisms and nutrients. Another suggestion is to allow grass to grow to three inches and then cut no more than one inch off the top. This is the “one-third” rule and helps to develop a deeper root system, which is a natural defense against weeds, disease and drought. Visit DEC’s Lawn Care web page for more information.
DEC also encourages homeowners to leave lawn clippings after mowing to improve the health of the lawn. Grass clippings are 80 percent water and contain two to four percent nitrogen, phosphorus, potassium, and other nutrients. Leaving clippings also saves homeowners time after mowing and reduces the amount of garbage thrown out. Grass clippings can account for as much as 10 percent of garbage.