Reducing Phosphorus Impacts to Waterways

Phosphorous is important for seed development, root growth and for maturation of your lawn.  It is, however, a primary water quality concern in Michigan.  An excess of fertilizer on lawns, sidewalks and driveways can make its way into lakes and streams by storm drains or over land when it rains.  As phosphorous adheres to soil particles, erosion can carry it directly into surface waters.  This can cause nuisance aquatic weed growth and algae blooms, effectively choking area waters.  Please, NEVER apply phosphorous fertilizers on lawns adjacent to lakes, rivers, streams or wetlands. 

Just one pound of Phosphorous can support the growth of about 750 pounds of algae! Excess phosphorus greatly speeds up the eutrophication process, and if not controlled, can cause a lake to 'age' more rapidly.  To improve and maintain lake and stream water quality, many counties in Michigan have adopted ordinances specifically forbidding the application of phosphorus to established lawns unless a soil test confirms a deficiency.

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Most soil in our area carries enough phosphorous to support a healthy lawn.  You can have your soil tested to see if your lawn, garden or fields need additional phosphorous.  If additional phosphorous isn't needed, you can purchase zero phosphorous fertilizer.  Fertilizer bags carry numbers giving the proportion of nitrogen, phosphorous and potassium in the mix.  For example, a 22-0-15 mixture has 22 percent nitrogen, 0 percent phosphorous and 15 percent potassium.  Always look for Zero in the Middle!