Pennsylvania's lawn fertilizer law: what it asks of you and your lawn company

Updated November 10, 2026 · KeystoneProGuide editorial team

Does Pennsylvania regulate lawn fertilizer?

Yes, and the rules apply to homeowners as much as to lawn care companies. The Department of Agriculture says the revisions to the Pennsylvania Fertilizer Law in July 2022 brought new responsibilities to homeowners and residents who fertilize their lawns. They must know and follow the law's limits on how much nutrient goes down, its restrictions on where and when, and the best practices written on the product label. A professional applicator works under the same rules.

The reason is water. Home lawns, the department says, make up 70% of Pennsylvania's 2 million acres of turfgrass, about 1.4 million acres, and nutrients that leave them end up in streams. The Montgomery County Conservation District lists fertilizer among the pollutants that runoff carries from properties into waterways.

What are the rules on where and when?

The department summarizes the restrictions this way:

Keep a 15-foot buffer from the top bank of lakes, ponds, wetlands and flowing water.
Do not apply near water, storm drains or drainage ditches.
Do not apply if heavy rain is expected.
Do not apply to paving or other impervious surfaces, and sweep any material that lands there back onto the turf.
Do not apply to frozen or snow-covered ground.
Use a properly calibrated device designed for fertilizer.
Do not use fertilizer to melt snow or ice.
Do not store or dispose of fertilizer in a way that could discharge to a waterway.

Since January 11, 2024, the department says, fertilizer labeled for turf must carry several of these warnings on the bag itself: not near water, storm drains or ditches, not before heavy rain, only on the intended site, and sweep granules off hard surfaces.

What about how much fertilizer goes down?

The law sets limits on nitrogen per application and restricts phosphate, and the label states the rate for each product. This guide does not repeat the figures: follow the label and the department's published limits, and let a soil test tell you what the lawn needs. Penn State Extension says most lawns benefit from some nitrogen each year, applied in mid to late spring and/or late summer to early fall, and that fertilizer with some slow-release nitrogen suits most lawns. The department describes enhanced-efficiency, or slow-release, fertilizer as a formulation that releases nutrients more gradually, which limits losses.

Why is phosphate restricted?

The department explains that phosphorus can bind to soil particles and move with runoff, and that high levels in water promote excessive algal growth, which harms aquatic life. Pennsylvania therefore restricts phosphate in lawn fertilizer. It is allowed when you are establishing, re-establishing or repairing turf, in enhanced-efficiency products, or in a site-specific amount when a soil test shows the lawn needs it. Starter fertilizers containing phosphate are sold wherever fertilizer is sold for those uses.

The department notes that this is why phosphorus-containing lawn fertilizer has become hard to find in stores. A lawn company proposing a phosphate product for an established lawn should be able to point to a soil test, or to one of the law's exceptions, as the reason.

Does a lawn care company need a license to fertilize?

Not for fertilizer alone. The department says a lawn care provider is not required to have a license or registration to use fertilizer in Pennsylvania, but must follow the label and all the nutrient rate and site restrictions.

The licence question turns on what else is in the bag. The department says a provider applying fertilizers that contain pesticides, such as weed and feed or pre-emergent crabgrass products, must have a pesticide license. That brings in the state's applicator rules: a commercial applicator must pass a core exam and a category exam, and work for a company holding a pesticide business license. Penn State Extension says the lawn category is 7, and that the company's BU license number must be shown on both sides of its vehicles.

What should you ask a lawn care company about the law?

The department suggests three questions:

Does the company test the soil to determine what your lawn needs?
What other factors does it consider when deciding how to treat your lawn?
Is it aware of the Pennsylvania Fertilizer Law, and does it comply?

Add a fourth of your own: does any product in the program contain a pesticide, and if so, who is the licensed applicator? The soil test itself is covered in should you test your soil.

Can you cut fertilizer use without losing the lawn?

The department's "watershed friendly" lawn strategies include several that cost nothing:

Return the clippings. A mulching mower puts grass clippings back into the soil as organic matter and nutrients.
Mow higher. Avoid removing more than 1 inch of blade at a mowing. The department says taller turf can increase root growth, drought tolerance and pest resistance.
Mix the grasses. Combining varieties such as creeping red fescue, hard fescue and turf-type tall fescue, or adding micro clover, can make a lawn hardier and reduce its nutrient needs.
Leave a buffer. Let native plants grow along a stream to stabilize the bank and filter runoff.

The department goes further and suggests replacing some or all of a lawn with native meadow, which it says can in the long term reduce maintenance and runoff. It adds that not every site suits a conversion, and that you should talk to local officials and neighbors first.

Where do you complain about a bad application?

To the Department of Agriculture. It investigates complaints about fertilizer that does not match its guarantee and about improper applications, through its Bureau of Plant Industry on (717) 257-6548. Pesticide complaints go to the department's pesticide program, on 1-717-772-5231 according to Penn State.

For how this law fits with the other rules on landscapers, see what Pennsylvania requires. To check a lawn company before hiring, see how to choose a landscaper, and local businesses are on the landscapers directory page.

Sources

Homeowners and Applicators, Pennsylvania Department of Agriculture
Fertilizer FAQs, Pennsylvania Department of Agriculture
Pesticide Applicators, Registered Technicians, and Certification Exams, Pennsylvania Department of Agriculture
Choosing a Qualified Pest Management or Lawn Care Company, Penn State Extension
Lawn Management through the Seasons, Penn State Extension
Rain Gardens and Barrels, Montgomery County Conservation District
Pesticide Application Businesses, Pennsylvania Department of Agriculture