Annual Rye Grass

Annual Rye Grass

One of the weeds that homeowners have to battle is annual ryegrass (Lolium multiflorum). Once a very popular cover crop, the annual ryegrass has transformed into a weedy nuisance in recent times. Also called Italian ryegrass, this annual grassy weed is difficult to get rid of especially as some of its biotypes have gained resistance to herbicides.

Annual ryegrass is an annual winter grass commonly found in most parts of the United States. It is still a very popular variety of grass and is often used as a forage grass or as a temporary cover crop to prevent erosion of soil.

It produces tufted vegetation that can last for up to 4 years if not appropriately controlled. Annual ryegrass can grow up to 3 ft tall. The leaf blades are broad for a grass, tend to be a bit shiny, and can be up to nearly a foot long.  

The annual ryegrass flowers from spring through fall. Before dying off in winter, it produces several seed heads, and seeds can mature quickly and fall off on the ground where they can germinate the next fall, continuing the cycle.

Seed Mix Contamination

The most common source of annual ryegrass contamination is turf seed mix. Many seed mixes contain some amount of ryegrass seeds. They are included as the ryegrass seeds germinate very quickly, sometimes within a week, and the grass establishes rapidly, especially during the fall and winter season. As the grass is very quick to germinate, it provides a very quick greening to the homeowners’ delight before turning into a problem!

Annual ryegrass is not a grass you want to use for your home turf. It produces clumpy tufts of grass, the leaf texture is very coarse, and it does not blend very well with other more attractive grasses such as Bermuda or zoysia. Another problem with the annual ryegrass is that it leaves many bare spots on the lawn and creates opportunities for other weeds to take over as well.

How to Manage Annual Ryegrass?

One of the best ways to manage any weed is to eliminate the source of contamination in the first place. Always use a high-quality seed mix, whether you are overseeding your lawn or establishing new turf. Many cheap quality seed mixes can have a large number of ryegrass seeds mixed in. Avoid using such blends, especially if you are overseeding the patchy portions of a lawn.

It is relatively difficult to control ryegrass contamination, especially in the cool-season grasses. However, as it is an annual grass, if taken proper care, it can be eliminated without much of a trouble.

Here are some tips to control the spread of this grassy weed:

  • Annual ryegrass loves water. Overwatering your lawn can be an invitation for ryegrass to grow. Always follow the golden rule of infrequent and deep watering.
  • As is many other weeds do, annual ryegrass also loves bare spots. Make sure that you do not mow your lawn too closely to leave bare spots and less dense turf.
  • Aerating your turf is generally a great idea. However, if you have annual ryegrass infestation, avoid aerating during the seeding periods of the weed to eliminate the possibility of spreading the seeds all over your lawn.
  • Any sighting of a lonely ryegrass plant should be promptly attended to. Take out the plant before it seeds and tries to uproot the plant without leaving any root in the soil.
  • Manually weeding out individual plants is still the best option. Although it is time and labor intensive, it is worth the trouble.
  • Overseeding is an excellent method to reduce the contamination of annual ryegrass. Make sure that the seeds used for overseeding are high quality and are not contaminated with any ryegrass seeds.
  • Selective herbicides can be an option as well if the infestation becomes a problem. We strongly recommend that you take professional help from a lawn service that specializes in weed control if you go this route.

Something to Take Away

Annual ryegrass is a really annoying weed. Once infested in your lawn, it can rapidly take over. Make sure that you are using high-quality seed mixes and always remember to get rid of the plant as soon as you spot it in your turf.