About the Ordinance

In 2011, Martin County adopted lawn fertilizer controls that restrict phosphorus and nitrogen all year long. Martin County’s strong fertilizer ordinance has served as a model for over 40 other communities along the Indian River Lagoon. Fertilizer restrictions aim to reduce the amount of harmful nutrients entering local water bodies, a crucial step toward improving and maintaining water and habitat quality.

  • APPLICATION BAN (June 1 – September 30): Fertilizers containing nitrogen (N) and phosphorus (P) should not be used on landscaping or lawns.
  • APPLICATION PERIOD (October 1 – May 30): Fertilizer containing phosphorus (P) is not allowed, and nitrogen (N) must be 50% slow release.

Additionally, vegetative material (including grass clippings), cannot be washed, swept or blown into stormwater drains, water bodies or impervious areas. The ordinance applies to anyone, personal or professional, landscaping in unincorporated Martin County. The fertilizer ordinance includes exceptions for agriculture, golf courses, and athletic fields, as well as for lawns where soil tests have shown a need for phosphorus.


To understand nutrient pollution and how you can help reduce it, you first need to understand watersheds. A watershed is an area of land that drains into a common body of water.

Within a watershed, each small body of water will flow into another body of water, creating one inter-connected system. Nutrients — primarily nitrogen and phosphorus — are key ingredients in lawn fertilizer.

When it rains, lawn fertilizer can wash into a watershed via nearby storm drains and canals that empty into the St. Lucie River and contribute to the growth of algae blooms.

Once in our waterways, excess fertilizers fuel the growth of algae blooms that block sunlight from reaching seagrasses, rob the water of oxygen and threaten underwater life.

Protect Our Lagoon

  1. Make sure the middle number, phosphorus (P), is zero, unless a soil test reveals a deficiency. 
  2. Make sure the nitrogen (N) listed on your fertilizer bag is 50% slow release.
  3. Do not use a fertilizer with nitrogen (N) and phosphorus (P) during the application ban period: June 1 – September 30.
  4. Fertilize only when rain is not forecasted; otherwise, fertilizer will wash away into the ground water and ultimately into our waterways.
  5. Keep a 25-foot, fertilizer-free buffer from all water bodies.
  6. Use deflector shields to keep fertilizer granules away from all impervious surfaces, fertilizer-free zones, no-mow zones, and water bodies.
  7. Keep all grass clippings and vegetative material away from streets, storm drains, and water bodies.

Download BeFloridianNow.org's Fertilizer Flyer