Are cover crops beneficial for yields?
This is an often asked question that has mixed results in scientific literature. There is geographic specificity to this answer. In the southeastern U.S., there is some good work that shows growing cover crops in rotation can provide yield increases (especially if you are rotating crop species — legume covers with grasses, grass covers with legumes). Remember though, that cover crops grown in the Southeast have a much longer growing period than cover crops grown at more northern latitudes.
In the Midwest, the yield benefit of cover crops to primary crops is not as consistent. We can find publications where yield increases are reported and others where there is no yield benefit (occasionally there is even a yield drag).
When cover crops are grown is important. Cover crops grown following wheat (more of an Eastern Corn Belt strategy) have a greater probability of providing a benefit than a cover crop that’s grown following a soybean and corn harvest (which becomes even more true as one moves further north). I would recommend consulting local extension personnel or retail agronomists to get guidelines on the right cover crops for your area, and more importantly how to manage them.
