Mich. Admin. Code R. 285.634.1
Rule 1. Plant nutrients in addition to nitrogen, phosphorus, and potassium when mentioned in any form or manner must be guaranteed. Guarantees must be made on the elemental basis. Sources of the elements guaranteed, and proof of availability must be provided to the director upon request. Except guarantees for those water-soluble nutrients labeled for hydroponic or continuous liquid feed programs, and guarantees for potting soils and lawn soils, the minimum percentages that will be accepted for registration or licensing, or both, are as follows:
Element | Percent |
Calcium (Ca) | 1.0000 |
Magnesium (Mg) | 0.5000 |
Sulfur (S) | 1.0000 |
Boron (B) | 0.0200 |
Chlorine (Cl) | 0.1000 |
Cobalt (Co) | 0.0005 |
Copper (Cu) | 0.0500 |
Iron (Fe) | 0.1000 |
Manganese (Mn) | 0.0500 |
Molybdenum (Mo) | 0.0005 |
Sodium (Na) | 0.1000 |
Zinc (Zn) | 0.0500 |
Mich. Admin. Code R. 285.634.1