Green manure

I have the delightful opportunity to occasionally work with the youth in the after school program at the Salvation Army. A couple of weeks ago, I told them we were going to be planting green manure. You should have seen the looks on their faces, which ranged from fear and curiosity to excitement and surprise. It was like looking at a roomful of emojis.

Most gardeners are familiar with cover crops. Green manure crops are the same thing.
When you till the cover crop into the soil before the next growing season, it is sometimes referred to as green manure. One can’t really plant manure, right?  If you are wondering why I left the word “crop” off the end of my statement about green manure to the Salvation Army kids, I did it intentionally to get their attention. And, it worked.

How do cover crops help our soil? In addition to maintaining soil fertility and health, these plants can also reduce soil erosion, suppress weeds, improve soil structure and even reduce insects. https://ipm.missouri.edu/meg/2011/8/Cover-Crops-and-Green-Manure-Crops/

How do you plant a cover crop in your annual flower garden or vegetable bed? We have to know what, when and how much. Since this is October and we have had our first frost, the best option here in Colorado right now is winter rye (Secale cereal). You can purchase seeds locally or through a seed supplier online. One source online sells the seeds for about $5 per pound.

Since we have waited until after the first frost to sow the rye, it will be easy to remove all existing vegetation from your annual garden. PlantTalk recommends raking the garden smooth, then broadcasting the seed at a rate of two pounds per 1,000 square-foot area. You can rake the area again lightly or sprinkle a thin layer of soil on top of the seed. One mistake I have made in the past is raking the seed in too aggressively. If you do this, you might end up with a lot of rye in one area and not so much in another.

Rye does best with adequate moisture. However, due to its deep root system, it can tolerate drought better than some of the other cover crops. In the spring, rye will start to flower when it receives 14 hours of sunlight per day. The goal is to incorporate the rye into the soil completely before this occurs. Once flowering begins, vegetative growth stops and the grass can take longer to decompose. https://www.uvm.edu/vtvegandberry/factsheets/winterrye.html

At the end of the growing season, shouldn’t we thank Mother Earth for all the nutrients provided from the soil? All the wonderful benefits and harvest we received in the form of our beautiful landscape, juicy vegetables and sweet fruit? We can do that by replacing nutrients in the form of organic matter. Plant some green manure today and make it a family affair.

Kelley Rawlsky has an M.S. in horticulture and is the director of Bringing People and Plants Together, an organization dedicated to bringing horticulture education and therapy to the community. For more information: PeopleAndPlantsTogether@gmail.com or follow us on Facebook.