Using inoculants N-fixing bacteria are fragile organisms. Inoculants need to be handled with care. Proper storage is critical. Make certain the inoculant is fresh and has been stored in a manner recommended by the manufacturer. Inoculation ahead of seeding is possible, but check with the manufacturer to see if the shelf life of the product will allow it.
Some seed treatments are toxic to inoculum.
Captan and PCNB are very toxic to inoculum. Vitavax is relatively safe up to 24 hours before seeding. Thiram produces effects in between these two groups. Planter box treatments using dry materials or auger treatments with liquids, fresh or frozen materials are both acceptable if they give good coverage of all seed. Competition is possible from native strains of Rhizobium bacteria which are less efficient than commercial inoculum.