What Is Sod? Types, Uses, and Growing Advice
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Reviewed by Kathleen Miller
Sod is a layer of pre-grown grass, including the soil and roots. They typically comes in rolls and are laid out to plant a fresh lawn. The advantage in starting a new lawn with sod over starting one from seed is how quickly you'll have the finished product.
Sod is more expensive than grass seed, so it's not for everyone. But there are some circumstances where sod is the most sensible way to plant a new lawn. Learn exactly what sod is, when sodding is better than seeding, and how to get the job done right.
What Is Sod Used For?
Sod is essentially grass that has already been grown and is now ready to layout. It's a much faster alternative to planting seeds and waiting for your grass to grow. Homeowners can use sod not only to start new lawns but also to repair bare patches and prevent erosion on slopes on new properties where there hasn't been time for landscaping yet. Sod also has commercial applications: Large operations like sports stadiums or golf courses can't be bothered with sowing seed to establish the vast stretches of perfectly-manicured green they need.
Benefits of Sod:
Sodding provides an "instant lawn," so sod is the way to go if time is at a premium. For example, if you're selling your property and the existing lawn is sub-par, it makes more sense to lay sod to replace it than to sow grass seed.
Likewise, if water run-off is causing a problem in your yard, sodding the hillside is a practical solution. It would take longer to build a French drain to address the issue.
After you've sodded a lawn, there's less irrigation for you to worry about than after seeding a lawn, because sod is already-established grass.
Types of Sod: Warm-Season vs Cool-Season
Your climate largely dictates whether you will want a warm-season sod or a cool-season sod. Warm-season sods grow actively during the warmer periods of the year. Cool-season sods grow actively during the cooler times of the year (spring and fall). It's necessary to match sod-type to your region; otherwise, you will have to look at brown grass for too many months out of the year.
Warm-Season Sod
Warm-season types are popular in the South because they can withstand the powerful summer heat. They're in danger of going dormant (turning brown) between 55 and 65 degrees Fahrenheit.
Bermuda grass (Cynodon dactylon) can grow in zones 7 to 10. It is a popular grass in the Southeast via both stolons and rhizomes. This makes it vigorous but also problematic: It tolerates foot traffic (dog and human), is drought tolerant, and grows well along the coast because of its salt tolerance. But it needs frequent mowing and often invades flower beds.
Zoysia (Zoysia spp.), thanks to newly developed cold-hardy varieties, can be grown in zones 5 to 10. It's especially popular in the South. It has qualities similar to Bermuda grass, but lacks the latter's salt tolerance. Another drawback with zoysia is that it produces a lot of thatch.
Centipede (Eremochloa ophiuroides) can be grown in zones 7 to 10 and is a favorite grass in the South from the Carolinas to Texas. Like zoysia, it's not as salt-tolerant as Bermuda grass but outperforms Bermuda grass in shade. It doesn't tolerate foot traffic but does tolerate acidic soil. Because it doesn't require much fertilization or irrigation, it's considered low maintenance.
St. Augustine (Stenotaphrum secundatum) can grow in zones 7 to 12. Like Bermuda grass, it's popular in the Southeast, especially common along the coast due to its salt tolerance. Its blades are bluish-green, wide, and flat. This grass has a creeping habit that allows it to form dense mats. Keep its soil evenly moist.
Cool-Season Sod
Cool-season sods are generally grown in the North because they stand up to the punishing cold of winter. They're in danger of going dormant when summer temperatures reach 90 degrees Fahrenheit.
Tall fescue (Festuca spp.) can be grown in zones 3 to 8 and has a clumping habit. It looks different from most other lawn grasses: It has wide, dark green wide blades that are coarse to the touch. It tolerates foot traffic and drought and doesn't produce much thatch, but it doesn't blend as well with other turf types in a lawn as most grasses do.
Kentucky bluegrass (Poa pratensis) can be grown in zones 3 to 7. Valued for its bluish-green color, it has distinct pros and cons. Benefits include its tolerance for foot traffic, its soft texture (great for bare feet), and its ability to bounce back from stress. But it's intolerant of heat, drought, and shade.
Perennial rye (Lolium perenne) can be grown in zones 5 to 7. It forms clumps and has light green blades. It is coarse and grows in a patchy habit. It should be fertilized monthly in spring and fall, but only until six weeks before the first frost is forcasted.
How Is Sod Grown?
Sod is grown from seed on a sod farm. To prepare the area, the farm tills the land to clear it and adds compost. A second tilling works the compost into the soil. After seeding and the work involved in caring for the sprouted grass (fertilizing, irrigation, mowing), the crop can be harvested in 10 months to two years (some types of sod take longer to grow than others).
Sod is removed from the ground using a sod harvester, a specialized device with two blades attached to a tractor. As the tractor runs over the area, one cut lifts the sod out of the ground, and another separates the grass into moveable units. The sod can be cut into either slabs or rolls. For rolls, two sizes (a large and a small) are typically created. The large rolls are several feet long and can't be installed without professional help. But the small rolls (ranging from 2 to 5 feet in length) can be installed by homeowners.
Tip
If you plan to lay sod in the fall, don't wait too late into the season to buy it. Doing so may leave you with few choices because suppliers start running out of stock at this time.
How to Choose the Right Sod
There are multiple things to consider before choosing a specific variety of sod for your lawn:
Price: Some types of sod are more expensive than others. Other factors, location, for example, need to be considered. Generally, you'll pay between $1.50 and $3.00 per square yard. Measure the size of the area you need to cover before ordering.
Growing Region: The type of sod you select should be suitable for your local climate and average weather. Generally, grow warm-season sods in the southern U.S. and cool-season sods in the northern U.S.
Care Requirements: Some types of sod aren't demanding in terms of light or water and aren't heavy feeders. Others are fussier about location and require regular watering and fertilizer to stay healthy. How low-maintenance you want your landscaping to be is part of deciding on a sod type.
Tips for Growing Sod
Sod should not be laid over existing grass. Sod roots need to be in direct contact with the soil. So when you lay sod over existing grass, the latter acts as a barrier, preventing the sod roots from making contact with the soil.
After planting sod, water it thoroughly every day for two weeks. To check that the soil is being saturated properly, peel up a corner of one of your sod strips (this won't hurt it), and feel the soil underneath the sod; it should feel damp but not muddy.
One month after planting, feed the sod with a high-nitrogen fertilizer. Feed a second time 30 to 60 days later. The first growing season will be the most high-maintenance. Your sod will be lower maintenance in the second season.
Frequently Asked Questions
What is the difference between grass and sod?
In a sense, there's no difference between sod and grass, because sod is grass. But "sod" is often used to refer specifically to a way in which grass is sold (as opposed to grass seed).
How long does sod last?
Sod that is properly cared for should last at least 10 years.
What is the best time of year to lay sod?
Early fall is the best time to lay cool-weather sod. For warm-season sod, the best time is early summer.
Read Next: Replacing Grass With a Garden Bed
Read the original article on The Spruce.
