You have probably seen mung beans before but didn’t even know what they were. This warm-season legume used by many as a cover crop is best suited to certain regions and soil types. Mung beans can be an additional cover crop species to add diversity to cover crop mixes.
Mung bean sprouts are popular additions to sandwiches and salad bars across the U.S., but it is not commonly known by its regular name.
I first heard about mung beans from Kelly Kettner, a grower from Muleshoe, Texas, who will be one of the speakers at the upcoming National Cover Crop Summit. Kettner raises mung beans as part of his 3-way cover crop mix.
Mung beans are very popular in India, eastern Asian countries and the Middle East. The most commonly grown variety in the U.S. was released by Oklahoma State University in 1962.
Mung beans were first domesticated in Persia more than 4,500 years ago. This short-season legume matures in less than 60 days and are heat and drought tolerant. Mung beans are also capable of thriving in a variety of soils, especially sandy loams in areas where conditions are dry. The crop does not tolerate soils that are wet or poorly drained.
This cover crop is a cousin to cowpeas and is mostly grown in Oklahoma and Missouri. Production in the U.S. is estimated to be about 100,000 acres and they’re typically planted in June, double-cropped after wheat or canola, and harvested in September.
As a legume that fixes its own nitrogen (N), mung beans do not need N fertilizer. By fixing N, mung beans help build up the nutrients in the soil, while also serving as a cost savings for the grower, as the additional input cost for fertilizer may not needed.
A 2016 study done in Montana found that higher seeding rates of mung beans in cover crop mixes improves their performance in terms of soil health.
Dale Strickler of Green Cover Seed notes that mung beans are excellent as a part of a grazing mix because the pods don’t split open at maturity like cowpeas, so growers who want something with late-fall protein will find the pods hang onto the plants much better.
Not only do mung beans fix N in the soil, they also produce moderate amounts of biomass and add a warm season broadleaf component to cover crop mixes. However, it’s important to find an effective seeding rate if you’re going to use mung beans in a cover crop mix because it may add to the overall cost. They are smaller-seeded than cowpeas but due to their size you can get more seed per pound, Strickler notes.
Growers looking for a dual-purpose cover crop component that can improve soils and benefit livestock grazing systems might want to check out what mung beans bring to the table.