Home Grown Nutrients
Henderson says he chose these particular crops for their ability to leave nitrogen in the soil after they are harvested.
Over time, the plant residue in the field turns into nutrient-rich organic matter in the soil and the plants’ roots loosen the soil, allowing for deeper soil moisture and improved biological activity in the soil. Carbon and nitrogen are two of the dominant nutrients farmers monitor in their fields. Crops are reliant on a proper balance of these nutrients to produce the best yields.
NRCS recommends an ideal carbon to nitrogen ratio of 24:1. Wheat stubble left in the field produces a carbon-to-nitrogen ration of 80:1. Thus, nitrogen has to be added to the soil to bring the ration back in balance. Cover crops in combination with no-till farming seldom require additional nitrogen to reach the ideal C:N ratio.
“In the past I have had to buy nitrogen to add to the soil,” he says. “But now, with legume crops like the guar beans, sesame seeds, cow peas and some others that have an 8:1 carbon-to-nitrogen ratio, I can essentially grow my own nitrogen.
“That is a big savings in itself,” he emphasizes.
Made in the Shade
Henderson says many farmers are hesitant to plant a summer crop in the middle of a dry spell.
“Hot, dry weather is exactly why you would want to plant a summer cover crop – to protect your soil,” he says.
Henderson explains that good soil bacteria and microorganisms that feed the plants die when soil temperatures get above 130 degrees.
“In this part of the country, it gets 114 or higher nearly every summer,” Henderson says. “That means the soil is 150 degrees and you have just killed your soil microorganism community.
“On a hot summer day, would you rather be sitting outside in the glaring sun or under the shade of a tree?” he asks.