As organic growers, we strive to feed the soil instead of only the plants. If the soil is healthy, plants have a better chance of thriving. Part of that process on our farm is giving the soil a rest from cash crops occassionally so that we can grow cover crops. These are crops like clover, oats, buckwheat and cow peas that we seed and when mature mow and plow back into the soil to feed the microorganisms that help make nutrients available to plants.
After our tomato crop this year, we planted cowpeas. Any legume such as cowpeas has this amazing ability to partner with Rhizobia bacteria, which is naturally occurring in the soil, to capture Nitrogen found in the air and put it into the soil. The grower knows this has happened by observing the roots on the legume once its mature. If there are nodules present on the roots, the rhizobia have colonized the roots and you know the the Nitrogen fixing is taking place! Furthermore, if you press the nodules and they exude a pinkish liquid, you know the process is complete.
I pulled up some of this cover crop this week to check and sure enough the pink nodules are present so its time to mow and tarp this cover crop so we can capture Nitrogen for the winter cover crop that will go in this tunnel.
