Legume Inoculation

Legumes such as beans, peas, clover and alfalfa are able to access (“fix”) nitrogen because their roots host symbiotic bacteria of the genus Rhizobium. Different legumes require different species of rhizobia to form a successful relationship. The plant roots feed the bacteria while the bacteria take molecular nitrogen from the air and convert it to a form that the plant can use.

Legumes take up nitrogen from the soil like other plants, and in fact do so in preference to the energy-intensive process of nitrogen fixation if soil nitrogen is plentiful. If you are growing leguminous crops in nitrogen-rich soil, inoculation may produce little yield benefit. However, nitrogen fixation cannot take place without the requisite rhizobia: if you are planting legumes in poor soil or planting a leguminous cover crop to build soil nitrogen, inoculation is non-negotiable.

Our legume inoculants do have a shelf life. We don’t ship expired inoculant, but inoculant ordered in fall or early winter may expire before spring. Like yogurt, inoculants do not instantly “go bad” when they hit their expiration date: they lose potency quite slowly, so it’s unlikely to be a problem. However, if you are ordering inoculant for the spring season and want the date to look good at planting time we recommend waiting until that same spring to order it.

Store inoculant in a cool, dry place out of direct sunlight. We recommend using fresh inoculant each time you plant a legume even if you have planted inoculated seed in the same spot before. Fresh inoculant ensures an immediate increase in bacterial populations. When you are ready to put the seed in the ground, moisten it with water, pour the inoculant over it and mix. Plant immediately if planting by hand; for machine-planting, you’ll need to let seed dry to prevent clogging, but plant as soon as the seed has dried.

Our inoculants do not contain genetically modified materials.

Organic Certification

Inoculants, soil amendments, fertilizers, livestock supplies and pesticides are labeled as:
OMRI: Organic Materials Review Institute. Most state certifying agencies, including MOFGA, accept OMRI approval.
MOFGA: Reviewed and approved by the Maine Organic Farmers & Gardeners Association Certification Services. Allowed for use on MOFGA-certified farms. Check with your certifier.
WSDA: Listed by the Washington State Department of Agriculture’s Organic Certification division for use in organic agriculture in Washington State. MOFGA has indicated that they will accept products on this list for their certification program. Check with your certifier.
Nat’l List: One-ingredient products on the NOP* List of Allowed Substances (subpart G of the Organic Foods Production Act, sections 205.601-606). Check with your certifier.
AYC: Ask your certifier. Has not been reviewed by a certifier, but the active ingredient is allowed. Ask your certifier.
Not Allowed: A few of the products we list are not allowed for organic production but we think they have a place in sensible agriculture and can be used when certification is not an issue.