All the gardening books and magazines tell you that legumes (peas, beans etc) are nitrogen-fixing plants that can feed themselves and enrich your soil.

What they frequently don’t tell you is that they don’t do it alone. For most of us it’s been a long time since biology lessons and we may have forgotten (or never learned) about symbiosis. Legumes need to form a relationship with soil bacteria called rhizobia before they can do their nitrogen-fixing thing.

Patrick at Bifurcated Carrots has already written a nice post on this subject, which includes links to a US company that supplies rhizobia (although no one calls them that) and a UK company that makes them. I’ve never seen them on sale, but I may simply not have been looking in the right places.

Which is why it’s nice to see that Mr. Fothergill’s have included packets of bacteria in their 2008 catalogue – under the name Bean Boosters. They have 3 different sorts (for broad beans, peas and mangetout, French and runner beans). The details on the website are sketchy, so I’ve ordered a paper catalogue to see whether that has any more information. It suggests that each packet of Bean Booster caters for up to 4 packets of pea/ beans. But I don’t know what that means.

If I get my act together I might try an experiment this summer and grow some peas/ beans with the bacteria and some without. But I may not have the space!