It's a fact: cover crops tend to make good farmers into great farmers and average farmers into bad farmers. Cover crops work. But, management is key and the learning curve can be steep. If you've been sitting on the sidelines in the past but are interested in jumping on the cover crop bandwagon, don't be intimidated. There are cover crop choices that will make your first foray into cover crops a profitable and enjoyable experience. My favorite cover crop for beginners is black oats and here are the top five reasons why.
They're easy to plant. Black oats have a fairly wide window of planting opportunity compared to other covers. Here in SC, we begin seeding ours behind corn in the middle of August and will plant them up until the end of November. Of course, the warmer weather promotes tillering so our seeding rate starts around 2 bushels per acre (when planted by itself) and trends up to around 3 bushels per acre by the end of November. They can be planted a number of ways, from drilling to broadcasting (with light incorporation). Also, black oats tiller faster than regular oats and other cereal grains, making them more forgiving in tough planting conditions.
They produce loads of biomass. Black oats' C-to-N ratio is lower than that of cereal rye but has similar biomass tonnage. What does this mean? The lower C-to-N ratio will allow the black oats to break down quicker than cereal rye, returning valuable nutrients and organic particles back into your dirt that can be used by the crop immediately following the cover crops. This also means that when nitrogen is applied to the cash crop following the covers, the nitrogen won't get "tied up" in trying to break down the cellulose of the cover crops but will contribute to the cash crop at a fairly rapid pace. The black oats will provide up to 8,000 lbs of biomass back to the land that they are grown on. Over time, this will help build organic matter, which is the holy grail of sustainable farming.
They're easy to terminate. I like cereal rye as a cover crop, too. But, one of the biggest problems farmers have with cereal rye cover crops is the speed at which they can get away from you. Once they grow too large, not only do you have to deal with tougher planting conditions due to the biomass, but the thick cellulose stalks are harder to kill. They also take longer to decompose, thus tying up scavenged nitrogen that we’d rather have available to our cash crops. Black oats don’t bolt: they're easily killed with roundup or mechanically via a roller/crimper and they decompose quickly for easy planting conditions. Check. Check. Check.
They provide tremendous ground cover. If planted early enough, black oats tiller quickly and become a true cover crop in the sense that the entire surface area around the plant is covered. Ground cover is huge for cash crops that follow cover crops. Ground cover cools the soil surface, which is a bigger deal than you might think. As I explained in “On the Offensive with Cover Crops”, at 70 degrees, 100% of soil moisture is used by crops while, at 95 degrees, only 15% of soil moisture is available. Ground cover makes a huge difference in soil cooling. A covered soil also helps suppress weeds.
They're super easy to grow for seed and yield much more than cereal rye and wheat do. We love growing black oats for seed. Why? We can plant them on marginal land, fertilize them and forget them. We tend to harvest them last and they hold up fairly well. Plus, when it comes time for harvest, our average yields on these crops are as follows: cereal rye: 25 bu/acre, wheat: 60 bu/acre, and black oats: 100 bu/acre. It takes a lot less land, inputs and work to get the quantity of bushels produced for our cover crop needs with black oats than it does with any other alternative. The black oats also seem to store better than cereal rye, as we’ve had trouble in the past with high heat killing rye’s germplasm in hot, humid grain bins.
Cover crops seem the buzz of the farming world these days. And, that's for good reason! However, it’s easy for a cover crop beginner to look at pictures of 9-way multi-species blends on Instagram and get overwhelmed. The thought of establishing a good stand and then managing the cover crops so that your cash crop is optimized can be more than a little intimidating. But, it shouldn’t be. Start slow. Start simple. And give black oats a try! You’ll be a better farmer for it and your land (and wallet) will thank you.