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Blackout Dates for Lawn Fertilizer Applications Begin November 16

ANNAPOLIS, MD ( November 7, 2022 )- The Maryland Department of Agriculture (MDA) is reminding citizens and lawn care professionals that fertilizer blackout dates authorized by Maryland’s Lawn Fertilizer Law begin November 16, 2022, and run through February 28, 2023. The blackout dates help protect local streams and the Chesapeake Bay from runoff during the colder months, when grass typically goes dormant and cannot benefit from the additional nutrients. Applying fertilizer to hard or frozen ground increases the risk of runoff into the storm drains that feed the Bay.

During the blackout dates, citizens are prohibited from fertilizing lawns with products containing nitrogen or phosphorus. From November 16 through December 1, 2022 lawn care professionals may apply up to 0.5 pound of soluble or insoluble nitrogen per 1,000 square feet to lawns that they manage. Potassium and lime may still be applied during the blackout period.

As a reminder, fertilizer products should never be used to melt ice on sidewalks, driveways, and other paved surfaces. Fertilizers that land on hard surfaces or frozen ground can easily wash into storm drains, creeks, and streams that empty into the Chesapeake Bay. 

Citizens and lawn care professionals may resume lawn fertilizer applications containing nitrogen and phosphorus on March 1, 2023, as long as the ground is not frozen or heavy rain is not predicted. A soil test is required before phosphorus may be applied to established lawns. 

Maryland’s Lawn Fertilizer Law requires lawn care professionals to be certified by MDA to apply fertilizer to lawns that they manage, or work under the direct supervision of an individual who is certified. In addition, licenses are required for individuals and businesses that fertilize turf. A list of certified lawn care professionals can be viewed here. Please visit this website for more information about Maryland’s Lawn Fertilizer Law and fertilizer best management practices.

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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