posted 10 years ago
Most likely you can't actually buy innoculum for the at all. That is only for large commercial crops like soybeans, and the strains used there are plant specific. You're better off just finding a Carob, or mimosa, or lucaena somewhere and just scrapping up a potfull of soil/humus from around the roots of the trees. That will supply the innoculum you need.
You also need to remember that nitrogen fixation is only really important in nitrogen deficient soils. If your soil is not already starved for nitrogen they will still do fine. I started my Carobs from seed, and didn't even bother collecting litter from under the seedstock trees. All my seedlings still had dark green leaves.