Inoculum for Legumes

Inoculum for Legumes

Choose from 17 different rhizobial inoculum strains including Baptisia, Dalea, Lupinus and many more. 1 bag will inoculate up to 1 pound of seed.  
Native legume species will show satisfactory growth without inoculum, but we recommend using inoculum if the proper type is available. The fixation of atmospheric nitrogen improves the long-term health of native plant communities and is especially important in low fertility soils. We suggest mixing inoculum with seed before planting or cold moist stratifying. See codes C & I in the Germination Codes online, within each species page, and in our catalog.

Prairie Moon Nursery furnishes our 'small packet' of inoculum at no additional charge for legume-seed orders of one ounce or less. However, after June 1st, 2020 we will be discontining this service.  We have found that many customers do not use inoculum and grow healthy vigorous plants.

: Add inoculant to dampened seed and mix thoroughly.
WHEN TO ADD: At time of moist cold stratification, or if direct seeding, as close to planting time as possible.
SPECIAL CARE: Protect inoculated seed from sunlight or drying winds - cover seed as quickly as possible with soil or mulch.
ALTERNATIVE METHODS: Inoculant can be mixed with potting soil when planting in flats or peat pots; directly in the seed furrows along with seed at time of transplanting; or to potted plants by making a hole with a pencil. Inoculum may also be added to potting mix for container grown plants or into the bottom of a hole when transplanting container grown or bare root seedlings.

2 Questions asked on Inoculum for Legumes

Q Chris DeRhodes • 04/05/2019 It is effective to apply inoculum to seedlings that have already sprouted in indoor containers? What about something like an existing Baptisia plant growing outside that was planted in post-construction exposed subsoil of questionable quality?
A Prairie Moon • 04/08/2019 Thanks for writing, Chris. The bacteria in the inoculums that we carry for legumes typically are already present in most healthy soils. They do not affect plant germination but do establish symbiotic relationships with developing roots to enhance the formation of nodules that absorb atmospheric nitrogen. Adding inoculum to soils is an effective way to introduce or increase the population of beneficial bacteria.
Q Maggie • 06/06/2019 Hello, do you offer inoculum for Thermopsis? Thanks!
A Prairie Moon • 06/06/2019 Hi Maggie! We do! It's the same as the Baptisia Inoculum. We'll provide genus-specific inoculum free of charge with legume seed orders of 1 oz or less.
*PLEASE NOTE: we are a mail order nursery and have no retail facilities, but you may pick up your order if prior arrangements are made. Pick up orders are subject to 7.375% MN Sales Tax.

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