All About Winter Rye Grass

Winter rye grass blades blowing in wind

The Spruce / Evgeniya Vlasova

Winter rye grass (or "ryegrass") is an annual grass best known for its use in agriculture. Not only do farmers grow it as a feed for livestock, but it is also harvested and processed to make rye bread and whiskey. It can, however, be useful for the home gardener, too. Winter rye grass is a type of grain, or "cereal," a fact suggested by its botanical name: Secale cereale. It is a plant that serves practical purposes rather than aesthetic ones, in contrast with the ornamental grasses; it is not a type of grass that you would grow in a lawn. Learn how to grow winter rye grass and how to use it.

Winter Rye Grass vs. Annual Rye Grass

Like winter rye grass, Lolium multiflorum is also an annual plant; in fact, it is commonly known as "annual rye grass." A popular use for annual rye grass is to overseed a lawn.

There is also a perennial form of rye grass called Lolium perenne. Mainly used as a lawn grass, its seed is commonly found in the grass seed mixes that you find at hardware stores for those who want to start a new lawn.

Best Uses for Winter Rye Grass for Gardeners

Winter rye grass is most useful to home gardeners as a cover crop. True to its name, a cover crop is a crop that you sow to cover a patch of ground. It is similar in this respect to a "ground cover," but, unlike a ground cover, a cover crop is used in a horticultural setting rather than in a landscaping setting. Some of the benefits in growing a cover crop are the following:

  • Weed control: A cover crop, densely planted, can take up the space that would otherwise be filled with weeds.
  • Fertilization: If you till a cover crop under when you are done growing it, it serves as a green manure.
  • Protection for your garden soil in winter: Leaving your garden bare after the harvest isn't ideal. Wind and water can erode your soil. Mulch is one option for protection, but a cover crop gives you an alternative to mulch.

There are several kinds of plants that can be used to sow a cover crop, but winter rye is one of the best. Tolerant of a wide range of conditions, it can be grown almost anywhere in the U.S. While all cover crops suppress weeds, in the case of winter rye, this function is aided by the plant's allelopathic quality. Its seed germinates quickly, and with its robust root system, it provides good coverage. It can also be planted later than many other cover crops.

When to Plant Winter Rye Grass

Timing is critical to the whole "cover crop" concept. You want to get it established before winter comes. At the other end of the process, when spring returns, you want to mow the cover crop and rototill it into the soil at the right time, too.

Winter rye grass is a cool-season type of grass, making fall a great time to plant it, which dovetails nicely with your needs as a gardener. The plant's love of cool weather not only allows it to become well established once planted in fall but also to put on additional growth quickly in early spring. That additional growth provides a large amount of green manure when tilled under. Its early maturation means that you can get the cover crop out of the way in time to plant your primary garden crops.

Winter rye grass is planted from seed. The seed is commonly sold in bulk at home improvement centers and at chains that cater to small farmers.

Winter Rye Grass Care

Winter rye grass seed can simply be broadcast by hand. Coverage of about 2 pounds of seed per 1,000 square feet is recommended, but err on the side of denser coverage if your goal is to suppress weeds. Once the seed is down, it needs to be covered with about 1 inch of soil. The easiest way to do this is to broadcast the soil (walking on the seed will not harm it). Water it in afterward.

Fortunately for you, winter rye grass is not a fussy plant to grow. It will grow in ground with a soil pH of anywhere from 4.5 to 8.0 (although it prefers a range of 5.0 to 7.0). Nor does it need to be fertilized: One of its virtues is that it can be planted in poorer soils than some of the other cover crops will tolerate.

Assuming an average rainfall, you should not have to water winter rye grass after germination. Your main concern at this point will be to keep an eye on your cover crop's growth in spring and terminate that growth at the right time. A cover crop is, by its very nature, temporary: If you planted it for winter protection, its job is done after winter is over. Moreover, if your timing is wrong with termination, you risk having winter rye grass outstay its welcome, due to its "grow-back" potential. This is one of its few drawbacks.

If you mow it too soon, it may grow back. But if you wait too long to mow it, winter rye grass will go to seed. If that seed drops, you will be stuck with a second generation that you don't even want (it will be in the way of your spring crops). The easiest solution is to monitor your cover crop for flowering and mow it as soon as you spot flowers. After mowing, till the winter rye grass under using a garden tiller.

Winter rye grass blades with light green wheat-lie ends closeup

The Spruce / Evgeniya Vlasova

Winter rye grass arching over in garden

The Spruce / Evgeniya Vlasova

Winter rye grass freshly cut with dew closeup

The Spruce / Evgeniya Vlasova

Rows of trimmed winter rye grass in field

The Spruce / Evgeniya Vlasova