Lolium

( LOH - lee - um )

At-A-Glance Information

Known commonly as Ryegrass, this genus of annual and perennial cool-season grasses are European natives. These are clumping grasses often mixed into lawn grass mixes for low-cost, large-area coverage. Use these grasses for erosion control and soil stabilization or as a high-traffic turf; it is commonly used for lawns, sports fields, and golf courses.

Lolium Species and Varietals

The genus Lolium is a member of the plant family Poaceae and includes 10 to 12 accepted species. These grasses are closely related to Festuca (Fescue) and Poa (Bluegrass). The best growing zones for Lolium vary depending on the species. For more information, see the species descriptions below. To find your zone, click here: Zone Map.

Lolium multiflorum (Italian Ryegrass, Annual Ryegrass, Australian Ryegrass, Australian Rye)
Best in USDA hardiness zones 3-9 or Sunset growing zones 1-24, this species is larger and coarser than perennial ryegrass, and is used to over-seed large lawn areas. It is fast growing and produces deep roots. Unmowed, these grasses can reach up to 5 feet tall and have a clumping habit. When used as a lawn, they can be mowed to between 1.5 and 2.5 inches. Pasture crop plants can be mowed to 4 inches. This species is considered highly invasive in California, the southeastern United States, and Australia.

Lolium perenne (Perennial Ryegrass, English Ryegrass, Ray Grass, Winter Ryegrass)
This species is a perennial bunchgrass that grows well in UDSA hardiness zones 3-8 or Sunset growing zones A2, A3, 1-6 and 15-17. They are vigorous growers with good wear resistance, and are ideal for over-seeding Bermuda Grass lawns. Best when mowed to about 2 inches tall. Individual grass clumps when left unmowed can reach up to between 1 and 3 feet tall at maturity. This species is considered invasive in Australia, New Zealand, and the western and southeastern to eastern regions of the United States.

Caring for Lolium

Lolium grasses are installed via seed or sod. Seed is highly cost-effective and ideal for larger areas, while sod offers an instant, weed-free lawn and is easier to establish on slopes. Plant Lolium, or Ryegrass, in a space in the landscape that receives partial shade or full sun; ideally, they appreciate between 6 and 8 hours of sun each day to grow well. Ensure that soil is well-draining, rich in nutrients, and has a pH of between 6.0 and 7.0 (slightly acidic to neutral). If local soils are particularly poor in nutrients or do not drain well, make sure to amend the planting area with plenty of organic compost before installing. Water new plantings regularly as they establish a strong root system in their new home. At maturity, most species perform well in consistently moist soils. They appreciate deep, infrequent waterings rather than daily shallow watering, requiring about 1 to 1.5 inches of water per week.

Fertilize yearly in early springtime by spreading out an application of 1/2 inches of compost over the lawn area. Avoid covering the grass blades entirely so the leaves are not smothered. Rake the compost in very gently, and then water to settle. Pruning is simple; remove any damaged, diseased, or dead foliage at any time during the growing season from free-growing clumps, and remove spent flower spikes to neaten up the appearance of plants and encourage reblooms. Deadheading will also discourage these plants from re-seeding in the garden. To maintain Lolium as a lawn, mow to a height of about 2 inches. Lolium plants can be annual or perennial. Annuals are typically used as a pasture crop, left in place at the end of the growing season to enrich the soil. Perennial species can survive for 3 to 5 or more years before needing to be re-seeded or replaced in the landscape.

Propagation

Lolium grasses can be propagated either by dividing existing plants or from seed. To ensure that your propagated plant will have the exact same qualities and characteristics as the parent plant, use the division method. If you would like to experiment and see what plant you can grow from seed, just keep in mind that it will not necessarily be the same as the parent plant. To propagate your Ryegrass, follow the instructions below:

Propagating Lolium by Seed

Keep in mind that the plant you get from seed will not necessarily mimic all of the characteristics of the parent plant. To propagate by seed, you will need a paper bag, a pot or tray filled with well-draining compost or other organic material, a spray bottle and a fork. The best potting medium for seed germination is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
Harvest the seeds. They are held on spiked inflorescences above the foliage. Once they have dried out and begun to split open, harvest the seeds. Cut them off of the plant, placing them in a paper bag. Harvest as many as you can, and place the paper bag in a dry, cool, dark area. They will begin to split open and release the seeds contained inside. Once they have been released, take them out of the bag and put them in a container so you can work with them.
Water your prepared seed tray or pot filled with soil, and ensure that good drainage is occurring. Place your seeds in your prepared pot or seed tray about a quarter inch to a half-inch under the soil surface. Cover them with soil and water with your spray bottle. Place your tray of seeds in a warm area that receives bright, indirect light. A greenhouse is the most ideal climate, but a planting tray inside a window will do as well. Germination usually takes 7-14 days from sowing.
Keep the seedling's potting medium moist, but not wet, by spraying the soil with your spray bottle. Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring (after the danger of frost has passed), when you can transplant it to its new home.

Propagating Lolium by Division
This type of propagation is relatively simple; you will need a clean shovel, mulch, fresh soil, compost, and pots (only necessary if you will be saving divided plants for transporting elsewhere). Division is best done in spring or fall. To propagate by division, follow these steps:

Gather your materials. Using a shovel, dig up your existing plant. Start from the outside and work your way in to avoid damaging the rhizome roots. Once you have worked it up out of the ground, lay it out.
Start to tease apart the roots with your fingers. Once the roots are untangled, separate your plant into segments, ensuring that each one has at least one thick rhizome section with two or three buds.
Prepare your pot(s) or new planting site(s) with amended, well-draining soil. You can either bring in new soil or simply amend your existing soil with compost to complete this task. Then, plant your divided rhizomes about an inch under the soil surface and water thoroughly.
Apply a thick layer of mulch over the new planting to protect it from cold weather as it acclimates to its new home. Then, enjoy watching it grow.

Problems and Pests

Certain species of Lolium are considered invasive in some regions; see the species descriptions above for more information. Check with local authorities before planting. Lolium grasses can be susceptible to developing issues with the following pests and diseases in the landscape: