Pronounciation: Lo-LIE-um per-EN-knee

Hardiness zones
Sunset All (dependingg on use)
USDA All (depending on use)

Landscape Use: Used primarily as an overseeded annuial cool season turf grass in Phoenix and other areas at lower desert elevation across the Southwest.

Form & Character: Soft, matting, refined, yet not delicate.

Growth Habit: This C3 perennial grass has a graminoid growth habit as a bunch grass, low and matting if regularly clipped. If not, the can grow to heights of 1 foot in a bunch-like, non-spreading manner.

Foliage/Texture: Medium bright green grass leaves that are folded in the bud, leaf margins are parallel, and abaxial leaf surface is glaborus, leaf blade tapers to a tip. The foliar collar usually has outgrowths (auricles) that clasp the stem; fine texture.

Flowers & Fruits: Flowers are spike like from 2- to 12-inches tall. Floral lemmas are awn-less in contract to annaul rye grass. Floral spikelets each contain about 3 to 10 florets.

Seasonal color: None

Temperature: Cold tolerant (will take frost and light freezes), but heat sensitive especially as air temperatures rise above 90^oF.

Light: During fall to winter and spring best grown in filtered shade to full sun.

Soil: Well-drained best

Watering: Should be watered regularly except during periods of heavy winter rains.

Pruning: Mow frequently when actively growing to maintain an tight, matted appearance. Mow once grass height reaches 2 to 3 inches depending on the intensity of turf use. Finished mow height should range from 5/8 inch to 2 inches.

Propagation: Seed; there are around 250,000 seed per pound. Sow perennial rye grass heavily, apply a mulch cover over the seed to protect it, and keep the underlying conditions moist for germination with frequent light irrigations.

Warning: Be prepared. Birds love to eat the seed.

Disease and Pests: Fungal diseases include rhizoctonia and Pythium. Note though that because perennial rye grass is not cultured as a perennial lawn in Phoenix, disease and pest pressures on it as an overseeded winter grass are minimal.

Additional comments: Domesticated perennial ryegrass for turf applications has been heavily bred for a short, matted habit of growth since 1961. Perennial ryegrass is a great utility grass that works well alone or in mixtures with other species. As a winter lawn in Phoenix, perennial rye grass seed is typically broadcast over closely-cropped (scalped) summer turf grass species such as Cynodon dactylon (Bermuda grass) during October. Once established, perennial rye grass will service well until the following May. In Phoenix, transition of a winter lawn to a summer lawn during late spring can be difficult. Perennial rye grass tolerates moderate foot traffic.

Miscellaneous tidbits: There are many named cultivated varieties of Lolium perenne that have improved environmental stress and disease tolerance. Perennial rye grass is also an important forage for cattle and sheep and is grown for silage and hay.