Phosphorus lawn fertilizer laws by state

As of October 2026, the 16 states below regulate phosphorus in lawn fertilizer, each checked against its current statute or rule. Seven of them limit what a turf-labeled product may contain, and the rest restrict applying phosphorus to lawns or how stores display it. Nearly all exempt new or repaired lawns and lawns where a soil test shows a deficiency, and the rules attach to products labeled for turf or lawns, so garden and houseplant products are often outside them.

Three kinds of rules

• Product rules. The fertilizer itself may not contain phosphorus, or must stay under a rate cap, unless it is labeled for an exempt use. If your bag is labeled for lawns and sold into the state, it has to comply. Maryland, New Jersey, Pennsylvania, New Hampshire, Virginia, Washington and Florida work this way.
• Application rules. The homeowner or applicator may not put phosphorus on turf except in exempt cases. The product can still be sold, but your label decides whether a buyer can use it legally. New York, Minnesota, Michigan, Wisconsin, Vermont, Massachusetts and Connecticut work this way. Illinois limits only applicators for hire.
• Retail display rules. Stores must shelve phosphorus products separately or post a sign. New York, Vermont, Massachusetts and Maine require this. Wisconsin bars displaying phosphorus-labeled turf fertilizer at all, allowing only a sign that it is available on request, and Washington bars display unless the product is also labeled for a permitted use.

State-by-state summary

A few details the table can't hold:

• New Hampshire caps retail turf fertilizer for new or repaired lawns, or lawns testing deficient, at 0.25 lb P2O5 per 1,000 sq ft per application and 0.5 lb per year. Natural organic turf fertilizer is capped at 1 lb of available phosphate per 1,000 sq ft per application. These limits took their current form on January 1, 2025.
• Pennsylvania's application rules allow enhanced-efficiency, natural organic or organic-based phosphorus at up to 0.25 lb of phosphorus per 1,000 sq ft per application and 0.5 lb per year, and allow a site-specific plan based on a soil test from the past 3 years.
• Maryland also bars fertilizer labeled as a de-icer, and New Jersey's label rule (but not its sales rule) also exempts products that deliver fertilizer under the soil surface to the roots.

Nitrogen limits often come with phosphorus limits

Several of the product-rule states also limit nitrogen:

• Maryland and New Jersey: consumer turf products may apply no more than 0.7 lb of water-soluble nitrogen and 0.9 lb of total nitrogen per 1,000 sq ft, with at least 20% slow-release nitrogen. Maryland adds annual and release-rate caps for enhanced-efficiency products.
• Pennsylvania: turf fertilizer for consumers must be at least 20% enhanced-efficiency nitrogen, with exceptions for liquids and readily available nitrogen products whose directions follow the state's application rates (0.7 lb readily available, 0.9 lb total per 1,000 sq ft).
• New Hampshire: retail turf fertilizer is capped at 0.7 lb soluble and 0.9 lb total nitrogen per 1,000 sq ft per application, and 3.25 lb per year.
• Florida: label directions may not exceed 0.7 lb of readily available nitrogen per application, 2 lb total in spring or summer, or 1 lb in fall or winter, with annual limits by region and grass species.
• Virginia: lawn maintenance fertilizer must apply nitrogen at rates consistent with the Virginia Nutrient Management Standards and Criteria.
• Vermont: turf-labeled fertilizer with less than 15% slow-release nitrogen may not be applied to turf.

The usual exemptions

• New lawns and repairs. Every state on the list makes room for phosphorus on new lawns, and many also for repairs, usually limited to the first growing season. Maryland, New Jersey and Pennsylvania require the product to be labeled for that purpose, and Vermont requires it to be labeled as starter fertilizer.
• A soil test showing a deficiency. The test window varies: 18 months in Vermont, 2 years in Connecticut, 3 years in Maryland, New Jersey, Massachusetts, Michigan, Minnesota and Virginia, and 36 months in Illinois, Washington and Wisconsin.
• Agriculture. Pasture, cropland, sod farms and other agricultural land fall outside "turf" or "lawn" in most of these laws.
• Golf courses. New Hampshire, Vermont and Connecticut leave golf courses out. Minnesota and Michigan allow phosphorus on courses that meet training or testing conditions.
• Organic sources, manure and compost. New York, Maine and Vermont exclude compost. Massachusetts excludes organic compost and natural organic fertilizer. New Jersey excludes manure and sewage-derived products, and Pennsylvania permits natural organic and organic-based products.

Lawn labels versus garden and houseplant labels

Several of these laws say directly that they stop at turf. Washington exempts interior house plants and flower and vegetable gardens. Virginia excludes products intended primarily for gardens, trees, shrubs and indoor plants. New York and Massachusetts define "lawn" to exclude flower and vegetable gardens, and Maine exempts fertilizer used for flower or vegetable gardening. Pennsylvania's application statements do not apply to products labeled for indoor use, potted plants, growing media or aquatic settings.

The trigger is the label. Maryland's and Pennsylvania's product rules apply to fertilizer "labeled for" turf, so an all-purpose 10-10-10 with lawn directions on the bag is likely inside them, while a houseplant food with no lawn directions is not. If one SKU carries both garden and lawn directions, have the label reviewed for each state.

Before you ship a lawn product

• Decide whether the label claims lawn use. If it does, the product rules above apply in those states.
• Use a zero-phosphate grade for maintenance lawn products. Florida requires a no-phosphate grade to show a zero guarantee.
• Label starter products for their exempt purpose, and check the rate caps in New Hampshire, Florida and Pennsylvania.
• Check nitrogen form and rates for Maryland, New Jersey, New Hampshire, Pennsylvania, Florida and Virginia.
• Add required statements. New Jersey and Florida require specific "do not apply near water" statements on turf products, and Pennsylvania requires application statements on turf fertilizer in packages of 1 lb or more.
• Watch local rules. Maryland bars local governments from regulating turf fertilizer, while Washington lets cities and counties be stricter but not looser. Florida's required label statement tells buyers to check county and city rules.

These limits sit on top of normal registration, licensing and tonnage reporting. See how to register fertilizer in every state and fertilizer label requirements, and for online sales into these states, selling fertilizer on Amazon and Shopify. Rules change, so confirm with each agency before you print a label or file.

Sources

• Conn. Gen. Stat. § 22-111yy (Chapter 427b)
• Fla. Admin. Code 5E-1.003, labels or tags (amended Jan. 27, 2026)
• 415 ILCS 65/5a, Illinois fertilizer application restrictions
• 38 M.R.S. § 419, Maine
• Md. Code, Agriculture § 6-222
• Md. Code, Agriculture § 6-223
• Md. Code, Agriculture § 6-224
• Md. Code, Agriculture § 6-201, definitions
• MDA Agricultural Commodities Registration Information
• 330 CMR 31.00, Massachusetts plant nutrient application requirements
• MCL 324.8512b, Michigan
• Minn. Stat. 18C.60
• N.H. RSA 431:3, definitions
• N.H. RSA 431:4-a, nitrogen content of turf fertilizer
• N.H. RSA 431:4-b, phosphorus content of turf fertilizer
• N.J.S.A. 4:9-15.8a, 4:9-15.13 and 4:9-15.13a (NJDA copy of the fertilizer law)
• N.Y. Environmental Conservation Law § 17-2101, definitions
• N.Y. Environmental Conservation Law § 17-2103
• N.Y. Agriculture and Markets Law § 146-g
• 3 Pa.C.S. §§ 6804, 6805 and 6813 (PDA copy of Chapter 68)
• 10 V.S.A. § 1266b, Vermont
• Va. Code § 3.2-3600, definitions
• Va. Code § 3.2-3607
• RCW 15.54.500, Washington
• Wis. Stat. 94.643