Laying Sod, Seeding, Sprigging and Plugging

Comparing the Four Methods
Seeding, a job that even beginners can tackle, is the least expensive planting option. Seeding requires less work than the other planting methods, but it does need longer-term care. In most regions, except the South, the best time to seed cool-season grasses is in late summer or early fall, when upper soil mean temperatures are 68 to 86 degrees F. This will allow your new turf to establish roots before the dormant winter period begins, while plant growth is vigorous and competition from weeds is low. Grass plants started in the fall will have a strong start in the spring and a root system sturdy enough to survive the following summer's hot, dry weather. In the South, spring and summer seeding are recommended for warm-season grasses (such as bahiagrass, centipedegrass, carpetgrass and buffalograss). The temperature of the upper soil should be between 68 to 95 degrees F. Check with your Cooperative Extension Service for recommended timing in your area.

Sprigging and plugging are methods typically reserved for warm-season grasses for which seed is not readily available, such as improved strains of Bermudagrass, zoysia, and St. Augustinegrass. Sprigging is best done during the height of the growing season, in spring and summer. Avoid planting when most weeds germinate (spring in the North and fall in the South). It's feasible to plant small areas by either sprigs or plugs. Plugging is generally a more reliable way to generate a new lawn than sprigging, but sprigging is easier to do and once rooted, sprigs will knit together faster to form turf. In general, sprigs take less time to grow turf than plugs do. Depending on the spacing and type of grass used, it takes several months to grow turf from sprigs and 6 months or more from plugs.

Sod requires more skill to plant, but it's okay to try your luck with small lawns or lawn sections. Sod offers several advantages over seed, plugs, or sprigs. It looks good immediately, and sodded lawns can be used much sooner than lawns planted by the other methods. Sod is better than seed for planting on sloping terrain, where seed would be washed to low areas after the first hard rain. In addition, sod is less susceptible to erosion while it is becoming established and makes it harder for weeds to compete. Sodding is best done in the fall or spring in the North and in the spring in the South. Plant the sod during cool, humid weather, because planting sod in warm dry weather will subject it to burnout. Do not plant sod later than one month before the first fall frost, because you want to give the grass time to establish roots before cold weather sets in.

Method 1: Laying Sod

Before you begin, apply a starter fertilizer that's high in phosphorus (such as a 2-1-1 or 1-1-1 ratio). Then lightly water the area where you will be installing the sod. Be prepared to begin work when your order is delivered. Sod can go bad quickly, especially if it begins to heat up or dry out. Have the pallets delivered to a shady spot. If you can't start right away, unroll the sod and keep it moist.

Lay sod over one section of lawn at a time. Begin by laying full strips along the outside edge (such as the sidewalk) of the area you plan to sod. Starting with a straight row will reduce the amount of cutting and fitting you'll do later. Next, work toward the opposite edge of lawn, usually the edge by your house. Use a sharp blade to cut as required. Make your last row a full-width strip, if possible. With contoured or irregular borders, lay the strips so that they overlap the border; trim away the excess later with a sharp knife or sharpened mason's trowel. The trowel is also handy for leveling minor irregularities in the soil. Again, try to install all of the sod the day it is delivered. If you have sod left over, unroll it in a shady spot, water it lightly, and use it the next day.

If you do sod your lawn in sections, you will need to lay sod against part of the existing lawn. You may find it helpful to use twine and stakes to mark the dividing line. Use the twine as a guide to cut a straight line in the existing turf with a manual or power edger. Lay sod to this edge and try to make a tight, unobtrusive seam.

If you're installing sod on a slope, start laying the sod at the lowest point. Stake each piece in three places to prevent slippage. Stakes should be equally spaced and set in from the sod strip's edges by at least 6 to 8 inches.

After installing the sod, firm it by rolling with a one-third full roller. If the roller is too heavy, it could cause the sod to slip. In hot weather, lightly watering the sod prior to rolling will also help prevent slippage. Follow rolling immediately with a thorough soaking--to a depth of 6 - 8 inches.

Method 2: Seeding

Apply a starter fertilizer (one with a nutrient ratio of 1-1-1 or 1-2-1) to the prepared surface, but do not till it in. Then spread the best seed you can afford at the rate recommended by the seed packager, usually given in pounds per 1,000 square feet.

In the absence of specific recommendations from the seed packager, the of rule of thumb for seed coverage is 15 to 20 seeds per square inch. Make trial passes with your spreader and adjustments until you achieve about 7 or 8 seeds per square inch. Then spread seed in two passes, first in one direction and then in a perpendicular direction, to ensure even coverage of about 15 seeds per square inch. Bulk up seed with vermiculite or sand if your spreader delivers too much seed even when set on the lowest setting. Follow up with a light raking to work the seed into the top 1/8 inch of soil; a light rolling with an empty roller will ensure good seed contact with the soil.

Seeding sloped areas is difficult because the seed tends to run to low points when it rains. One solution is to contract with a landscaper who has hydroseeding equipment. Hydroseeding involves spraying a suspension of fertilizer, mulch, and water onto the prepared surface. Apply frequent light waterings to hydroseeded surfaces to keep them from drying out.

Method 3: Sprigging

There are two ways to plant sprigs by hand. You can broadcast, or stolonize, sprigs over prepared soil at a rate of 5 to 10 bushels per 1,000 square feet, cover with 1/4 to 1/2 inch of soil, and then press the sprigs into the soil by rolling. Or, you can plant the sprigs (sprigging)in shallow furrows, 1 - 2 inches deep and 6 to 12 inches apart, depending on the grass variety and the sprig producers spacing recommendations. Plant sprigs in furrows, end-to-end at 4 - 6 inch intervals, and cover with soil. Be sure a portion of each sprig remains exposed to light - ideally one-quarter of its length. Then lightly roll or tamp the planted area to press the sprigs into the soil.

Method 4: Plugging

Plant plugs every 6 -12 inches in furrows 6 -12 inches apart. Or plant them in holes spaced 6 -12 inches apart in each direction. If you're digging individual holes, using a bulb planter will make the job go quicker. Plant slower-spreading grasses, such as zoysiagrass, 6 inches apart because of its slow growth rate. Grasses that spread more quickly, such as St. Augustinegrass or Bermudagrass, may be planted farther apart. You can purchase plugs or make your own from unwanted areas of turf. Use a golf-green cup cutter to cut circular plugs, or use a sharp knife, such as a machete, to cut 2-inch square plugs.