A fertilizer label may not bear a statement that connotes or implies that certain plant nutrients contained in the fertilizer are released slowly over a period of time, unless the controlled release components are identified and guaranteed at a level of at least 15 percent of the total guarantee for that nutrient.
The following types of plant nutrients may be labeled as controlled release plant nutrients:
"Controlled release" is the preferred term, however the terms "water insoluble," "coated slow release," "slow release," "controlled release," "slowly available water soluble," and "occluded slow release" are accepted as descriptive of these products, provided that the manufacturer can show a testing program approved by the department substantiating the claim.
Until more appropriate methods are developed, Association of Official Analytical Chemists (AOAC) International method number 970.04 (15th Edition), or the appropriate AOAC International method in a subsequent edition, must be used to confirm the coated controlled release and occluded controlled release plant nutrients and others whose slow release characteristics depend on particle size. AOAC International method number 945.01 (15th Edition), or the appropriate AOAC International method in a subsequent edition, must be used to determine the water insoluble nitrogen of organic materials.
When nutrients in a fertilizer are coated, or occluded to obtain controlled release properties, then the guarantees for those components must be shown as footnotes rather than as a component following each nutrient as indicated in items A to C.
Fertkote 10-15-20 | |
Guaranteed Analysis | |
Total Nitrogen (N) | 10% |
2.5% Ammoniacal Nitrogen | |
2.5% Nitrate Nitrogen | |
5.0% Urea Nitrogen* | |
Available Phosphate (P2O5) | 15% |
Soluble Potash (K2O) | 20% |
Sulfur (S) | 14% |
Plant nutrients derived from:_____ | |
* ___% Controlled release urea nitrogen from _____ |
Fertkote 10-15-20 | |
Guaranteed Analysis | |
Total Nitrogen (N)* | 10% |
2.5% Ammoniacal Nitrogen | |
2.5% Nitrate Nitrogen | |
5.0% Urea Nitrogen | |
Available Phosphate (P2O5) | 15% |
Soluble Potash (K2O) | 20% |
Sulfur (S) | 14% |
Plant nutrients derived from:_____ | |
* ___% Controlled release nitrogen from _____ |
Fertkote 10-15-20 | |
Guaranteed Analysis | |
Total Nitrogen (N)* | 10% |
2.5% Ammoniacal Nitrogen | |
2.5% Nitrate Nitrogen | |
5.0% Urea Nitrogen | |
Available Phosphate (P2O5)* | 15% |
Soluble Potash (K2O)* | 20% |
Sulfur (S) | 14% |
Plant nutrients derived from: _____ |
* The nitrogen, phosphate, and potash materials in this product have been coated to provide 9.0 percent coated controlled release nitrogen (N), 13 percent coated controlled release available phosphate (P2O5), and 18 percent coated controlled release soluble potash (K2O).
If a fertilizer material or fertilizer mixture contains recognized and determinable forms of water soluble nitrogen with controlled release properties, the guarantees for those components, if claimed, must be shown as footnotes rather than as a component in the nitrogen breakdown, as indicated in items A and B.
Slow Fertilizer 20-0-0 | |
Guaranteed Analysis | |
Total Nitrogen (N) | 20% |
8.0% Urea Nitrogen | |
2.0% Other Water Soluble Nitrogen | |
2.9% Slowly Available Water Soluble Nitrogen* | |
7.1% Water Insoluble Nitrogen | |
Plant nutrients derived from: _____ | |
* Controlled release nitrogen from _____ |
OR
Slow Fertilizer 20-0-0 | |
Guaranteed Analysis | |
Total Nitrogen (N) | 20% |
8.0% Urea Nitrogen | |
4.9% Other Water Soluble Nitrogen* | |
7.1% Water Insoluble Nitrogen | |
Plant nutrients derived from: _____ | |
*___% Controlled release nitrogen from _____ |
Note: If other recognized forms of water soluble nitrogens are listed in the nitrogen breakdown, the term "other" must precede the "water soluble nitrogen*" footnoted breakdown. The word "organic" may be used in the nitrogen breakdown where appropriate.
Minn. R. agency 105, ch. 1510, FERTILIZER LABELS, pt. 1510.0416
Statutory Authority: MS s 17.725; 18C.121