Blue lyme grass, the sand grass that looks like rye

Seaside view through leaves and seed pods of blue lyme grass

Sand ryegrass key facts

Botanical nameLeymus arenarius, Elymus arenarius
Common name – sand ryegrass, lyme grass
Family – Poaceae

Typegrass
Bearing – arched
Height – 4 to 5 feet (1.20 m to 1.50 m)

Planting density – 4 to 6 plants per sq. yard (m²)
Exposure – full sun Soil – any type
Flowering  – from June to August

Leymus arenarius owes its name to its strong resemblance to rye, especially the seed panicles. Since it quickly becomes invasive, it’s important to take a few precautions when planting it. Nonetheless, this is the perfect plant if your goal is to cover or stabilize an embankment. In addition, its blueish foliage will add an original touch of color to your garden.

Planting sand ryegrass

Leymus arenarius can cope with any type of soil. It does, however, require full sun exposure to truly thrive, though part sun is possible. For it to settle in faster, we recommend planting in fall, following these steps:

  • Three small sand rye grasses recently planteddig a hole 6 to 8 inches deep;
  • set the grass in the center of the hole;
  • backfill the planting hole, pressing it down well at root level.

Smart tip : sand rye grass is a grass that might quickly become invasive if it’s planted in sandy soil. To prevent this issue, you’ve got two option:

  • either you set up a rhizome barrier (more expensive, but very effective);
  • or you plant your grass in large plastic basins with a few holes drilled in the bottom, which you can bury to the rim.

Both techniques work well to contain roots and control spread.

Caring for Leymus arenarius

As is the case for many grasses, sand ryegrass requires nearly no care at all. All you’ve got to do is cut back the clump at the beginning of spring to renew leaves with new growth.

Propagating sand ryegrass:

To multiply a clump of Leymus arenariusjust separate it in fall:

  • unearth the clump with a spading fork;
  • break the clump apart with your hands or with a sharp spade;
  • transplant split portions following the guidelines listed above.

Diseases and pests:

Leymus arenarius is a resistant grass. It thus resists all diseases and pests.

Uses and landscaping

Landscaping uses or blue lyme grass include stabilizing sand dunesAs mentioned at the beginning of the article, sand rye grass is ideal for embankments: whether you simply want to cover it or stabilize it against erosion. However, another idea is to use it in a flower bed or along edges, as long as you remember to set limits upon planting so it won’t spread.

On top of these uses, its capacity to resist drought and sea spray make it an excellent choice for a coastal garden.

Regarding companion plants, you might want to look into the following for your Leymus arenarius : other grasses and perennials such as veronica or red heuchera, the colors of which pair well together.

The gray-blue leafage of blue lyme grass stands out against darker companion plants

Smart tip

If you like creating dried flower bouquets, you’ll appreciate knowing that just like rye, sand ryegrass is very well suited to this art.


Image credits (edits Gaspard Lorthiois):
Unsplash: Palle Knudsen
CC BY-SA 2.0: Ann-Sophie Qvarnström
CC BY 2.0: K M
Public Domain: Val Def