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MDA Reminds Marylanders to Protect Local Waterways and the Chesapeake Bay by Following the Lawn Fertilizer Law

ANNAPOLIS, MD – The Maryland Department of Agriculture (MDA) reminds homeowners and lawn care professionals that they can make a difference for local streams and the Chesapeake Bay by following Maryland’s Lawn Fertilizer Law.

The law took effect October 1, 2013 with the goal of protecting the Chesapeake Bay from excess nutrients entering its waters from a wide range of non- agricultural sources including golf courses, parks, recreation areas, athletic fields, businesses and hundreds of thousands of urban and suburban lawns. The law applies to both homeowners who fertilize their own lawns and lawn care professionals hired to apply fertilizer to residential, business and public properties.

“Turf grass is the largest crop in the Chesapeake Bay Watershed,” said Maryland Agriculture Secretary Joe Bartenfelder.  “Research shows that the way we care for our lawns, like any crop, can make a difference for the Bay.”

Lawn care professionals must be licensed and certified by MDA to apply fertilizer to the lawns that they manage. This helps ensure that they understand the science behind turf management and the environmental practices they will need to follow to protect waterways from excess fertilizer. MDA encourages homeowners to verify that their lawn care provider is certified by visiting

The law helps homeowners and professionals maintain healthy lawns without using unnecessary amounts of nutrients. It prohibits most lawn fertilizer products from containing phosphorus—a key nutrient that contributes to the Chesapeake Bay’s “dead zones.”  It also limits the amount of nitrogen contained in lawn care products and requires part of this nitrogen to be in a slow release form.

Maryland has about 1.1 million acres of turf grass – most of it in single family residences. That represents 18 percent of the state’s total land area and more than any single agricultural crop. Lawn fertilizer accounts for 44 percent of all fertilizer sold in Maryland.

Homeowners can make a difference for the Bay this spring by following these best management practices: 

  • Skip the spring fertilizer. Fertilizing lawns in spring promotes excessive top growth at the expense of roots.
  • Sharpen lawnmower blades. A cleaner cut looks better and is healthier for the grass.
  • Raise the cutting height of the mower. Taller grass shades out weeds and needs less water. A three inch cut length is ideal for most lawns.
  • Leave grass clippings on the lawn. They provide free fertilizer all season long.

If you fertilize:

  • Follow the directions on the fertilizer bag.
  • Learn about soil testing. Visit for seasonal and yearly fertilizer recommendations.
  • Do not apply phosphorus to lawns unless a soil test indicates that it is needed.
  • Do not apply fertilizer to sidewalks or other impervious surfaces. Clean up excess fertilizer.
  • Keep fertilizer applications 10 to 15 feet from waterways.
  • Do not apply fertilizer if heavy rain is predicted.

For more information, visit www.mda.maryland/fertilizer.

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Contact Information

If you have any questions, need additional information or would like to arrange an interview, please contact:
Jessica Hackett
Director of Communications
Telephone: 410-841-5888