Market Development for Mushrooms and Pet Food Rule

The United States Department of Agriculture (USDA) Agricultural Marketing Service (AMS) published a final rule aimed at clarifying the standards for organic mushrooms and pet food. If you are engaged in organic mushroom production, pet food handling, or related activities, you will be impacted by this rule change. Potentially affected entities may include, but are not limited to, the following:

• Organic mushroom producers (including organic spawn producers);
• Organic pet food manufacturers;
• Individuals or business entities that are considering organic certification for pet food or mushroom production (or related activities, such as spawn production);
• USDA-accredited certifying agents (or “certifiers”), inspectors, and certification review personnel.

For organic mushroom operations, the topics addressed by this rule include:

• mushroom substrate and spawn media composition;
• sourcing of mushroom spawn; and
• composting requirements for organic mushroom production.

For organic pet food operations, the topics addressed by this rule include:

• composition and labeling requirements; and
• use of certain synthetic substances, including taurine, in organic pet food.

To keep you well informed and prepared for these changes, we have established a timeline of key activities:

• Mid-Summer 2026:

• Self-assessment: PCO will send a self-assessment worksheet to all PCO-certified operations that will be impacted by this final rule. This will detail the changes and enable you to assess the potential impact of the MDR rule on your operation.

• Late Summer 2026:

• Training Videos: Look out for our announcement about upcoming training videos that will be posted to PCO’s website.

• Late Fall 2026:

• Revised Organic System Plan (OSP) forms: PCO will send you a revised OSP that aligns with the requirements of the MDR rule. You will only need to update questions impacted by the regulatory change. These will need to be submitted to PCO prior to the implementation date. PCO will communicate the exact due date upon issuance.