David M. Kopec, Extension Turfgrass Specialist

Installing sod provides an instant lawn, but only when it is done correctly. It is a common misunderstanding that all grasses used for sod cannot be used to seed a lawn, or that grasses established by seed cannot be used to produce a sod.

Sod is used to achieve a quick establishment of a new or renovated lawn. It can also be used to replace dead patches in a lawn.

Grasses used for sod are almost always those that produce a bound soil from rhizomes (underground shoots) or stolons (above ground runners). These structures hold or bind the soil and turf together. The result is a tightly-knit soil. Grasses that produce upright shoots from a single crown are weak sod-producing grasses.

Warm Season Sod: (low and mid-elevation areas)

By far, the most popular warm season grass is that of bermudagrass. Certain bermudagrasses that do not make seed, must be established by growing vegetative parts. This includes establishment by sodding, sprigging or plugging.

The following popular bermudagrasses do not make seed and are available as sod or sprigs.
(1) Tifway (419) bermudagrass
(2) EZ Turf or Midiron bermudagrass
(3) Tifgreen (328) bermudagrass
(4) Santa Ana bermudagrass

All bermudagrasses produce both rhizomes and stolons, which make them excellent candidates for sod.

The following St. Augustine and zoysia grasses do not make seed and may be available as sod.
(1) Palmetto St. Augustine (stolons only)
(2) El Toro zoysia grass (rhizomes and stolons)

There are other varieties available of bermudagrass, zoysia grass and St. Augustine. Always check with the nursery and/or sod grower for what is available in your area, as these can change from time to time.

Cool Season Grasses: (mid and high elevation)

The predominate sod forming grass here is Kentucky bluegrass. This grass produces underground rhizomes, which knit the soil and plants together, making a tight sod.

There are over 100 varieties of Kentucky bluegrass available commercially. Locally, you may be able to select from 5-6 KBG varieties. When two or more varieties of KBG appear in the same sod, it is called a blend. A typical blend may include Adelphi and America sod. Otherwise, the KBG sod can be a single variety only, such as Glade Kentucky bluegrass.

Kentucky bluegrass sod sometimes includes small amounts of other species of grass. For example, they may include 65% Kentucky bluegrass, 20% perennial ryegrass and 15% creeping red fescue. When another species is added to bluegrass, the sod is then referred to as a mixture. The ryegrass adds a quick cover to the sod and the creeping red fescue adds a shade tolerance component. The ryegrass itself is a bunch-type grass (tillers only) and depends on the bluegrass to hold the sod together. More often, KBG sod is a blend of two or more KBG varieties.

Special Cases:

Sometimes tall fescue or perennial ryegrass is available as sod. Tall fescue is more like ryegrass in that is produces short tillers and does not have coarse underground rhizomes or above ground stolons. Sod growers sometimes grow netted-sod of tall fescue or ryegrass. A plastic netting is installed on the ground which is covered by soil and seed. When the grass cover is mature, the sod is then cut with the plastic net intact. This holds the sod together for transport and installation.

Netted sod is sometimes used for St. Augustine grass as well. Since only stolons are produced, added sod strength is provided by the netting. This is usually a result of growing season length and sod-cut scheduling.

Bermudagrass sod is sold in the fall and winter with ryegrass overseeded into it already. This is referred to as overseeded sod.

The ryegrass should die out in the summer and the bermudagrass should then take over.