Reduce the unnecessary application of phosphorus to lawns, and reduce pollution in the river!
Phosphorus is naturally abundant in the soils of southeast Michigan. Water runoff from fertilized residential lawns is the primary source of phosphorus contaminants entering the Huron River. During normal lawn watering or natural rain storms, unnecessary phosphorus washes into the storm drains. These empty into local streams and the Huron River, without filters or treatment.
Starting in January 2012 a new Michigan Law, Public Act 299 of 2010, takes effect. It prohibits the application of fertilizers containing phosphorus to turf grass (with exceptions).
In the meantime the City of Ann Arbor, Pittsfield Charter Township, City of Ypsilanti and Ypsilanti Township in Washtenaw County, Hamburg Township in Livingston County and Commerce and West Bloomfield Townships in Oakland County have local ordinances in place. Read more about it in the brochure below.
How to Identify Phosphorus-Free lawn fertilizer.
On the outside of product packaging you will see a sequence of three numbers. The first number indicates nitrogen content, which promotes top growth on plants. The middle number indicates phosphorus, for root growth. The last number indicates potassium, for producing strong stems and resistance to disease. If you are looking for a phosphorus-free fertilizer, the middle number must read “0″. As a general rule, look for turf grass fertilizers with zero phosphorus and avoid lawn and garden fertilizers, which are very high in phosphorus.
More River-Friendly Lawn Care Tips
Make a clean sweep.
Keep fertilizer on the lawn and off hard pavement. Immediately sweep up any spills, especially on sidewalks and driveways, and clean those surfaces with a broom not a hose. Never apply fertilizer right before a rain storm. Fertilizer that washes away from your sidewalks, driveway, and lawn enters the storm drain system, which directly connects to local creeks and the Huron River.
Apply less fertilizer, less often.
If you fertilize your lawn once each year, fall is the best time. In the fall, fertilizer can help your lawn repair itself from summer damage and prepare for optimal growth in the spring. In all cases, only apply fertilizer during warmer months when your lawn is no longer subject to freezing temperatures, generally April 1-November 15.
Create a ”no fertilizer” zone.
Avoid applying fertilizer within 25 feet of any wetland, stream, waterway or stormwater retention or detention basin.
Put your lawn to work.
Maintain the lawn at a minimum height of three inches and, when you mow, cut no more than one-third of the height of the grass. Taller grass has a deeper, healthier root system, is more tolerant of drought, and resists weed infestation. When you mow, mulch the clippings back into the lawn. This adds nitrogen and organic matter to the soil, and prevents compaction (thatch).
Get your soil tested.
Learn what your lawn and garden need for optimum health and growth. In early spring (late March through mid April) you may participate in the Soil Testing program provided at a low cost through your County Michigan State University Extension Agent. It is easy, and agents provide individual recommendations based on your soil test results.
In the Soil Testing program, you dig up soil samples from your yard and drop them off at participating retailers, where they are forwarded to the University Extension service and analyzed. You will receive an analysis of the soil to detemine the optimum nutirents needed in a fertilizer for your particular soil. Call your County MSU Extension Agent for a list of participating retailers and current fees.
Simply following the general directions listed by the manufacturer on a package of commercial fertilizer can lead to overapplication of the products, and, for soils in this region, excess phosphorus application. Excess phosphorus, nutrients and pesticides that are washed off fertilized yards along with stormwater causes problems when they make their way into our creeks and rivers. Soil testing also helps watershed residents determine exactly what nutrients are needed, which saves time and money for the homeowner.
- Lawn Talk: Fertilizing Schedule for Home Lawns has lawn care information for Northern Illinois (which is a similar area to southeast Michigan) of the University of Illinois Extension Service.
- Fertilizing Landscape Plants is a fact sheet from the University of Ohio Extension service.
- Responsible Fertilizer Practices for Lawns is a report of the University of Minnesota Extension Service, division of “Turfgrass Management for Protecting Water Quality.”