Annual ryegrass is ideal for areas that experience cool climate conditions like the northern areas of the United States and in the transition zone. However, this type of grass has a short lifespan that lasts for a single growing season. So, when does annual ryegrass die?
Annual ryegrass will die naturally in late spring or early fall at the end of the growing season. Prolonged harsh weather conditions like extreme daytime temperatures (below 50 degrees Fahrenheit or above 90 degrees Fahrenheit) can also cause it to die.
When Does Annual Ryegrass Die?
Annual ryegrass is one of the grasses that stay green in winter but it only lasts for one season. Further, it’s not tolerant to extreme temperatures and it dies when temperatures are too hot or too cold.
Here is typically when annual ryegrass will die:
1. Dies off naturally in late spring or early fall
Annual ryegrass has a relatively short lifespan, it will die off naturally in late spring or early fall. The time of death coincides with the time the grass is planted. If you want a green lawn throughout the year, over-seed a warm-season grass with annual ryegrass in late spring.
In the Southern Atlantic Coast, Texas, Gulf Coast, and Midwest of the United States, annual ryegrass is usually a fodder crop. Over-seeding perennial grass or warm-season grass with annual ryegrass will extend the grazing season into winter.
2. Dies off in hot temperatures above 90 degrees Fahrenheit
Annual ryegrass is drought tolerance. However, it cannot withstand temperatures above 90 degrees Fahrenheit (32.2 degrees Celsius) for a prolonged period of time. Temperatures above 75 degrees Fahrenheit (24 degrees Celsius) will cause it to enter dormancy.
As the temperature continues to rise, the grass will stop growing. The blades will start to change color from green to brown. Eventually, the high temperatures will kill the grass completely regardless of daily watering.
3. Dies off in low-freezing temperatures
Annual ryegrass is vulnerable to extreme temperatures, it will not thrive in areas that receive temperatures below freezing. High humidity and melting snow create unwanted moisture that is detrimental to the grass. It can lead to bacterial and fungal infections.
In temperatures below freezing, annual ryegrass will change color from green to brown and die off completely. Annual ryegrass thrives in the temperature range of 50 to 65 degrees Fahrenheit (10 to 18 degree Celsius).
When to Plant Annual Ryegrass
Plant annual ryegrass in fall or spring when the temperature range between 50 and 65 degree Fahrenheit (10 to 18 degree Celsius). Planting at this time will ensure fast germination and quick establishment of the grass. Early establishment in the northern parts of the US enhances resilience against drought.
Annual ryegrass germinates well in both warm and cool soil. Prepare the soil in advance by tilling it to a depth of 6 inches and raking it free of rocks and other debris. Brake the large clots and fill the dips. Be sure the soil is well drained prior to seeding.
Fertilize the soil with fertilizer rich in nitrogen and phosphorus. Nitrogen helps to boost the initial growth while phosphorus promotes better root development. Be sure not to under or over-fertilize the soil. Generally, it is recommended to apply 1lbs. per 1,000 square feet of lawn.
Supplement rainwater with irrigation to ensure your lawn is getting at least 2 inches of water per week. How often to water grass seed will depend on the type of soil. Water daily until the seeds germinate.
As the grass establish, reduce watering gradually to once or twice a week depending on weather conditions.
Once the lawn grass has fully established mow regularly at the recommended height of 1.5 inches. During the time of heat and low rainfall, increase the mowing height to 2.5. Use a mulching blade when mowing to conserve soil moisture content.
If you’re establishing annual ryegrass for pasture, allow it to attain desired height before cutting or feeding it to your animals.
Does Annual Ryegrass Come Back Every Year?
The short answer to this question is no, annual ryegrass does not come back every year. Unlike perennial ryegrass which comes back multiple seasons, annual ryegrass lives only for a single growing season. It is usually planted in spring or fall and will die at the same period the following year.
Although when given proper care and growth conditions, it can reseed itself. Rake to remove debris from the last season, and fertilize and water your lawn to give it an opportunity to reseed itself for the next growing season.
However, annual ryegrass will require yearly reseeding even if it reseeds itself. Reseeding this type of grass is beneficial to farmers or gardeners who are utilizing it as a cover crop to improve soil fertility or as pasture for grazing.
When planting annual ryegrass for forage, it is ideal to practice crop rotation. Planting the same crop in the same place year in and year out will deplete nutrients and lead to a build-up of pests and diseases.
You can rotate grass with legume plants such as soybeans to replenish the soil with nutrients.
Is Annual Ryegrass Good for Lawns
Annual ryegrass is not best for permanent lawns due to its short lifespan. It’s a single-season grass that needs to be reseeded after each year. However, it is a temporal cool-season grass that is ideal for over-seeding warm-season grass such as Bermuda.
It provides a green lawn during winter when the warm-season grass enters into dormancy. Annual ryegrass can also provide a temporal solution for controlling soil erosion on a newly constructed lawn. It offers the best covers for bare soil to prevent wind and water runoff erosion.
Annual ryegrass is a versatile crop that is useful for other purposes such as:
Good cover crop
Annual ryegrass has a positive impact on the health of the soil. It is helpful in regaining fertility in farms where the soil has been depleted of nutrients. It has a dense root system that breaks up into the soil to provide ample aeration.
The roots penetrate deep into the soil to obtain nitrogen and bring it back up on the surface. It helps to bring the nutrients within reach of other plants.
Good for forage
Annual ryegrass is not only good for lawns or soil covering, but it’s also ideal for forage. It’s rich in proteins, digestible fiber, and other nutrients that are essential to livestock. Different livestock such as cattle, sheep, and goats all graze on annual ryegrass.
Final Thoughts
Annual ryegrass is a cool-season grass ideal for over-seeding warm-season grasses like Bermuda to provide a green lawn in winter. It’s also a good fodder crop for livestock as well as an ideal cover crop to control soil erosion. Unfortunately, it is a one-season grass that dies in spring or early fall and you have to reseed it yearly.