Iowa Code § 200.20 (2026)
Phosphoric acid, nitrogen, and potash requirements
1. Except as provided in subsection 2, a person shall not sell, offer for sale, or distribute any of the following:
a. Phosphatic fertilizer containing less than eighteen percent available phosphoric acid (P2O5).
b. Nitrogen fertilizer containing less than fifteen percent total nitrogen (N).
c. Potash fertilizer containing less than fifteen percent soluble potash (K2O).
d. Mixed fertilizer in which the sum of the guaranteed analysis of total nitrogen (N), available phosphoric acid (P2O5), and soluble potash (K2O) totals less than twenty percent.
2. Subsection 1 does not apply to any of the following:
a. A specialty fertilizer.
b. A fertilizer designed to be applied and ordinarily applied directly to growing plant foliage to stimulate further growth. [C77, 79, 81, §200.20] 2000 Acts, ch 1082, §2; 2025 Acts, ch 134, §17 Subsection 2 amended \n