Fertilizer
Labeling Requirements for Bagged Fertilizer
Wisconsin requires that bagged fertilizer products meet state labeling requirements. Common labeling problems include bagged products listing only a product grade with no guaranteed analysis or fertilizer grades with guarantees for secondary nutrients or micronutrients.
Requirements
To comply with Wisconsin's fertilizer regulations, all bagged fertilizers, including packaged custom mixed fertilizers, must be conspicuously labeled with the following information:
- Brand or product name
- N-P-K grade
- Guaranteed analysis
- Net weight
- Name and address of the licensed manufacturer/distributor
Fertilizer Grades
The Wisconsin Fertilizer Law defines "grade" as the percentage guarantee of total nitrogen, available phosphorus (or available phosphate), and soluble potassium (or soluble potash). A more common way is to refer to the percentage of N-P-K.
Example: 9-23-30 means 9% nitrogen, 23% available phosphate and 30% soluble potash.
Guaranteed Analysis
The guaranteed analysis tells the user the guaranteed percentage of the nitrogen, phosphate and potash within the product. The product cannot contain more or less of a listed guarantee. To ensure the guaranteed analysis is correct, the Wisconsin Department of Agriculture, Trade and Consumer Protection randomly samples and tests fertilizers each year.
Label Example
| SUPERGRO SUPREME |
| 19-19-19 |
| Guaranteed Analysis |
| Total Ntirogen (N) |
19% |
| Available Phosphate (P2O5) |
19% |
| Soluble Potash (K2O) |
19% |
| Net Wt. 50 lbs. |
Manufactured by:
The Fertilizer Company
Anywhere, USA |
Secondary Nutrients and Micronutrients
Bagged fertilizers can contain secondary or micronutrients such as zinc, copper or calcium. However, these secondary or micronutrients must be properly listed on the product label.
You cannot list additional plant nutrient guarantees within the grade statement. For example, a bagged fertilizer contains 5% zinc. The label cannot state "9-23-30-5Zn."
What is acceptable is to follow the grade statement with the secondary or micronutrient percentage. The secondary or micronutrient can also be part of the product or brand name such as "9-23-30 with 5% Zinc" or "SupremeGro 19-19-19 with 5% Zinc."
If secondary and/or micronutrients are claimed to be present in bagged fertilizer, the percent claimed must appear in the guaranteed analysis and meet the minimum amount as required by law. The table below lists the minimum amounts for each secondary and micronutrient. Secondary and micronutrients must appear using the elemental form and the format as listed in the table. These requirements are also outlined in ATCP 40, our fertilizer rules.
| Element |
Percent |
| Calcium (Ca) |
1.00 |
| Magnesium (Mg) |
0.50 |
| Sulfur (S) |
1.0 |
| Boron (B) |
0.02 |
| Chlorine (Cl) |
0.1 |
| Cobalt (Co) |
0.0005 |
| Copper (Cu)) |
0.05 |
| Iron (Fe) |
0.10 |
| Manganese (Mn) |
0.05 |
| Molybdenum (Mo) |
0.0005 |
| Sodium (Na) |
0.10 |
| Zinc (Zn) |
0.05 |
These labeling requirements promote uniformity in labeling of bagged fertilizers, as well as informing consumers of the plant nutrient values claimed to be present in the fertilizer. Bagged fertilizers that are found to be in violation of Wisconsin's fertilizer regulations are subject to warning notices and fertilizer stop sales.
For more information about labeling requirements for bagged fertilizers, contact the fertilizer program at (608) 224-4541 or send an email.
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