ANNAPOLIS, Md. — The Maryland Department of Agriculture is reminding residents and lawn care professionals across the state, including those in Southern Maryland, to follow Maryland’s Lawn Fertilizer Law as spring lawn care activities begin in 2026.
The law aims to reduce nutrient runoff from non-agricultural sources such as home lawns, golf courses, parks, recreational areas, athletic fields and businesses into local streams, rivers and the Chesapeake Bay. Excess nutrients contribute to water quality issues in the bay watershed.
“Fertilizer products provide nutrients for healthy grass, but overusing them can harm local streams and the Chesapeake Bay,” said Maryland Agriculture Secretary Kevin Atticks. “By following Maryland’s Lawn Fertilizer Law, residents and lawn care professionals can maintain healthy lawns and cleaner, healthier waterways.”
The reminder was issued April 1, 2026, after the fertilizer blackout period ended March 1. Applications containing nitrogen or phosphorus can resume as long as the ground is not frozen and heavy rain is not predicted.
Homeowners who hire lawn care professionals must ensure the company is certified through the department’s Turfgrass Nutrient Management Program or works under a certified supervisor. The department maintains an up-to-date list of certified professionals on its website.
For those who maintain their own lawns, the department offers these key practices: Skip spring fertilizer applications if the lawn appears healthy. Fall is the preferred time to fertilize cool-season grasses common in Maryland, such as fescues and Kentucky bluegrass.
Sharpen lawnmower blades regularly to prevent tearing grass blades, which can weaken the turf. Mow at a height of about three inches to shade out weeds and help the soil retain moisture. Leave grass clippings on the lawn, as they return nutrients naturally and act as free fertilizer throughout the season.
When fertilization is necessary, first test the soil to determine actual nutrient needs and whether lime is required. Soil testing information is available through the University of Maryland Extension. Always read and follow the label directions on the fertilizer bag.
Follow the University of Maryland Extension’s lawn fertilizer schedule. Do not apply phosphorus, shown as the middle number on the fertilizer bag label, unless a soil test confirms it is needed. If any fertilizer lands on sidewalks or driveways, sweep it back onto the grass immediately.
Maintain a buffer of 10 to 15 feet from any waterways when applying fertilizer. Never apply product before a heavy rain forecast. The annual fertilizer blackout dates remain in effect from November 16 to March 1, during which most nitrogen and phosphorus applications are prohibited for homeowners.
The law, passed in 2013, limits nitrogen rates and restricts phosphorus use to protect the Chesapeake Bay. A single nitrogen application may not exceed 0.9 pounds per 1,000 square feet, with additional limits on soluble nitrogen. Phosphorus applications are capped and prohibited without a demonstrated soil need.
Southern Maryland residents, where many properties drain toward the Patuxent River and other tributaries feeding the bay, can play a direct role in improving local water quality by adopting these practices. Charles County, St. Mary’s County and Calvert County homeowners benefit from the same statewide rules.
Additional details on the Lawn Fertilizer Law and best management practices are available on the Maryland Department of Agriculture website. The University of Maryland Extension site provides region-specific lawn care recommendations suited to Maryland’s climate and soils.
Certified professionals have completed training and testing on proper application techniques and bay-friendly practices. Using certified services helps ensure compliance while achieving good lawn results.
The department encourages everyone to make informed choices this spring. Simple steps such as higher mowing, leaving clippings and timing applications correctly can produce strong turf with less environmental impact.
As warmer weather arrives in Southern Maryland, following these guidelines supports both attractive lawns and the long-term health of the Chesapeake Bay, a vital economic and ecological resource for the region.
The Maryland Department of Agriculture continues to promote education on nutrient management to meet state goals for bay restoration. Public cooperation with the Lawn Fertilizer Law has contributed to measurable progress in reducing non-point source pollution over the past decade.
Residents with questions about certification or soil testing can contact the department or visit local University of Maryland Extension offices serving Southern Maryland.
