OMRI Listed® Products


Refined Boron for Organic Farming

U.S. Borax: OMRI Listed for Organic Crops

For organic growers who require refined boron, U.S. Borax fertilizers are listed appropriate by the Organic Materials Review Institute (OMRI). This international nonprofit organization determines which input products are acceptable for use on certified organic crops under the USDA National Organic Program, the Canadian Organic Standards, and the Mexico Organic Products Law.
As OMRI Listed products, U.S. Borax fertilizers are an appropriate fertilizer and soil amendment for organic crops that are boron deficient. OMRI is ISO 17605 accredited as a material review organization, so certifiers can accept the OMRI Listed Seal anywhere in the world. For more information about OMRI, visit

Other Organic Registration Certificates

U.S. Borax refined boron products are also certified by several other organic industry organizations. For more information about how we support organic growers, contact your local U.S. Borax distributor.

U.S. Borax, part of Rio Tinto, is a global leader in the supply and science of borates—naturally-occurring minerals containing boron and other elements. We are 1,000 people serving 650 customers with more than 1,800 delivery locations globally. We supply around 30% of the world’s need for refined borates from our world-class mine in Boron, California, about 100 miles northeast of Los Angeles. Learn more about Rio Tinto.

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