Does ProPeat Meet Wisconsin’s Phosphorus and Environmental Fertilizer Regulations?

Wisconsin’s turf fertilizer law limits the use, sale, and display of fertilizers containing phosphorus or available phosphate on turf. In practice, that means you generally cannot apply phosphorus fertilizer to established lawns, parks, and fields.

There are two main exceptions: establishing new turf, and lawns or fields where a soil test shows a phosphorus deficiency. In those cases phosphorus may be applied as allowed, ideally documented by the soil test.

The law also prohibits applying turf fertilizer to frozen ground and to impervious surfaces like sidewalks and driveways (where it would wash into storm drains). Keeping product on the turf and off the pavement is both the law and good practice.

ProPeat’s lawn and turf blends such as 17-0-4 and 10-0-10 carry zero phosphorus — the “0” in the middle number — so they’re formulated for legal use on established municipal turf.

For new turf or a soil-test exemption, keep the supporting records. If you manage multiple sites, building compliant blends into your standard program keeps every application on the right side of the rule.