In the chart below, you can see color-coded bands that pertain to climatic zones. In the accompanying guide to growing ideal cover crops, the Pioneer and DuPont agronomists determined that annual ryegrass was not recommended for use above Indiana, except in Michigan surrounded by lakes Huron and Michigan.
But here’s the catch. If the extreme temperature and wind chills hit annual ryegrass uncovered, it can certainly kill it off, or knock it back significantly. What is key to know, however, is that if the plant has snow cover to protect it from the icy blast, it can survive winter perfectly well.
In southern Canada, Ontario and Quebec specifically, lots of farmers use annual ryegrass each year. Their usual snowfall almost guarantees a healthy winter for annual ryegrass. Farmers in Minnesota and North Dakota also find annual ryegrass a viable cover crop even with their harsh winters, again, because of adequate snowfall.
In the report’s other graphic, showing the attributes of different cover crops, it shows annual ryegrass as ideal for a variety of reasons, namely for scavenging nitrogen, busting up compaction, preventing erosion and building organic matter. Click here for more information on growing and managing annual ryegrass as a cover crop.