RSA 431:4-b Phosphorus Content of Turf Fertilizer.

I. No no-phosphate fertilizer sold at retail for use on turf shall have an available phosphate level in excess of 0.5 percent.
II. No turf fertilizer sold at retail that is intended for use on newly established or repaired lawns, or for lawns testing deficient in phosphorus shall exceed an application rate of 0.25 pounds P2O5 per 1,000 square feet per application and 0.5 pounds P2O5 per 1,000 square feet per year.
III. No natural organic turf fertilizer shall exceed a per application rate of one pound of available phosphate per 1,000 square feet.