OMRI Listed: what the seal on garden products means

The Organic Materials Review Institute, OMRI for short, is a nonprofit founded in 1997 to evaluate materials for use in organic agriculture. It describes itself as the only independent nonprofit dedicated to input materials used in organic production. Its reviews are accredited to ISO 17065 by the USDA Quality Assessment Division, which assesses OMRI every year.

OMRI does not write the rules. It reviews products against standards set by others: the USDA National Organic Program in the United States and the Canada Organic Regime in Canada. When the regulators update those standards, OMRI updates its own manuals to match.

A product that passes is OMRI Listed and may show the OMRI seal. The list is long: OMRI's main directory has more than 10,000 products listed to the U.S. standards, and both the online search and the downloadable lists are updated nightly.

This is the label on this site that is most often misread, so it is worth being blunt.

A manufacturer applies and submits the product for review. OMRI review panels make the final decision on whether a product is listed. OMRI reports that, on average, 10% to 15% of the applications it receives do not make it through.

Each listed product is assigned a use class, such as Crop Fertilizers and Soil Amendments, and a category, such as Potting Soil. Some categories carry restrictions that limit how or when the product can be used. All three appear on the product's OMRI certificate.

Listing is not permanent. Companies must complete a renewal questionnaire and pay fees every year, and a missed renewal removes all of the company's listed products. They must also tell OMRI at least 60 days before changing a product, including its formula. OMRI may carry out inspections as well.

The two labels sit at different points in the chain. USDA Organic is for the things a farm produces: food, seed, fiber. OMRI Listed is for the things a farm uses to produce them. In OMRI's words, certifiers focus on the food and fiber products on store shelves, while OMRI verifies the substances used in organic production.

For a certified organic farm, the listing is a shortcut, not a permission slip. USDA instructions allow certifiers to rely on reviews from accredited material review organizations like OMRI, but OMRI is clear that the farm's certifying agent must be informed and always has the final say.

For a home gardener there is no certifier involved. The seal simply tells you the ingredients were checked against the organic standards, which is more than an unverified "organic" or "natural" claim on a bag can tell you.

In the garden aisle, mostly: on fertilizer, potting soil and compost, pest control and lawn care products. OMRI also lists livestock health care products and processing materials such as sanitizers, which home shoppers rarely see.

If you are setting up beds for the first time, our guide on how to start an organic garden explains where inputs fit in.