Planting a lawn entails selecting the turfgrass, selecting the method of establishment, properly preparing the soil, planting the turfgrass, and performing post-planting maintenance.

Turfgrass Selection

Cool season turfgrasses--Kentucky bluegrass, perennial ryegrass, tall fescue, fine fescues, and creeping bentgrass--are very commonly used in the Midwest, especially in the northern two thirds of the region. Cool season turfgrasses grow best when soil temperatures are between 50· and 65·F and when air temperatures are between 60· and 75·F. These conditions occur most commonly in spring and autumn in the Midwest. Without irrigation, cool season turfgrasses may become dormant during the high temperatures of summer. These grasses are easily established by seeding.

Warm season turfgrasses--zoysiagrass, bermudagrass, and buffalograss--are sometimes used in the southern portion of the Midwest. Zoysiagrass and bermudagrass lack cold tolerance and are poor choices for growing in northern areas. Warm season grasses grow best when soil temperatures are between 70· and 90·F and air temperatures are between 80· and 95·F. Thus, these grasses grow actively during summer's heat. From mid-fall through mid-spring, these grasses are brown, dormant, and unattractive. Many Midwesterners feel this dormant appearance is undesirable. Zoysiagrass and bermudagrass are most commonly established vegetatively by sod, plugs, sprigs, or stolons. Buffalograss is usually started by seed.

The previous unit, Turfgrass Selection , provides additional information.

Establishment Methods and Timing

Determining the lawn establishment method is an important first step in the establishment process. In the Midwest, lawns are normally established by seeding or sodding; zoysiagrass plugging is also used occasionally.
There are both advantages and disadvantages to seeding a lawn. A common method of establishing a lawn is seeding, which involves planting grass seed on a prepared seedbed.

The advantages of seeding are:

• the desired species or cultivars can be used;
• the turf plants develop in the environment in which they must ultimately survive; and
• establishment usually costs less than for sodding or plugging.

The disadvantages of seeding a lawn are:

• the appropriate times for establishment are limited;
• the turf is usually slow to develop into a quality stand;
• reseeding areas with poor germination may be required;
• quality seed may be difficult to obtain in some areas;
• rain or irrigation may wash seeds off slopes;
• weed encroachment is often a problem; and
• a constantly moist seedbed is required during germination.

Sodding entails placing squares or strips of growing turfgrass and the adhering soil onto a final planting site. The strips or squares are tightly butted to one another to produce a complete cover of turfgrass. Kentucky bluegrass, creeping bentgrass, zoysiagrass, bermudagrass, buffalograss, and occasionally tall fescue can be established by sodding.

The advantages of sodding a lawn are:  

• an "instant" lawn is planted;
• sodded lawns can be safely trafficked sooner than seeded lawns;
• dust and mud are reduced;
• erosion control is achieved;
• sod can be planted any time during the growing season (provided the ground is not frozen and water is available); and
• good sod is weed free.

The disadvantages of sodding a lawn are:

• the cost is higher than for seeding;
• choice of turfgrass species and cultivars used in sod production is limited;
• sod is not produced in shaded environments;
• a large volume of water is required during establishment;
• incompatibilities between sod farm soils and soils at the planting site can cause sod to perform poorly;
• sod may shrink, allowing weeds to invade between pieces; and
• the speed of sod rooting changes with the season.

Although it appears there are fewer advantages than disadvantages to seeding a lawn, do not discount the importance of species/cultivar choices and development in their ultimate planting site. For example, obtaining perennial ryegrass or fine fescue sod will be difficult, perhaps impossible, in most areas of the region. If these species are desired in the lawn, seeding is the only way to establish them. In addition, soil incompatibility sometimes develops when sod is grown on soil that is different from that of the lawn area. Soil incompatibility can result in poorly rooted sod that has little tolerance to environmental or pest stresses. Thus, in many situations, the advantages of seeding may outweigh the advantages of sodding.

Plugging is sometimes used to establish zoysiagrass in the Midwest. Plugs are 2- to 4-inch diameter pieces of zoysiagrass with the adhering soil. They are planted 6 to 12 inches apart in a well-prepared planting bed and often take up to 3 years to fully establish and fill in completely.

Seed turfgrass lawns comprised of Kentucky bluegrass, perennial ryegrass, fine fescues, or tall fescue during spring or late summer and early fall . Late summer and early fall (August 15 to September 15 in central Illinois) is considered to be the best time. In the fall, weed competition is reduced, temperature s are appropriate for rapid growth and development, and grass seedlings have plenty of time to establish a good root system before the following summer's heat. Spring (April in central Illinois) establishment can also be successful. It is important, however, that adequate irrigation be available during summer's heat.

The preparation steps (identical for seeding, sodding, or plugging) are:
1. Control weeds at the planting site.
2. Rough grade the site and remove debris.
3. Conduct soil tests.
4. Amend the soil as necessary.
5. Work and thoroughly mix the amendments into the soil to a depth of six inches.
6. Fine grade the site.

Eliminating weeds, especially perennial grassy weeds, will reduce competition with developing turfgrasses. Herbicides are valuable for eliminating weeds prior to lawn establishment. Consult the Cooperative Extension Service for a current list of recommended lawn care chemicals.

After eliminating weeds from the site, rough grade the area to facilitate surface drainage. Generally, a 1 to 2 percent slope (a drop of 1 or 2 feet for every 100 feet of run) away from buildings is adequate. Remove all debris brought to the surface by rough grading. Debris may include tree roots, stones, and leftover materials from construction.

If topsoil is needed at the planting site, incorporate it into the existing soil during rough grading. The final depth of topsoil should be at least 2 inches. Avoid using topsoil taken from sites that have recently been treated with agricultural herbicides; these herbicides could be detrimental to turfgrass establishment.

Soil testing provides a valuable means to determine if soils can support turf growth. For a small fee, commercial testing laboratories will evaluate soil pH, phosphorus, and potassium levels in a basic test. In addition, many other soil fertility and textural tests are available at an additional cost. Recommendations for corrective measures are also offered by many soil test laboratories.

Collect samples for testing during the growing season when soil temperatures are above 50·F. Samples should be 2 to 4 inches deep and the same size in diameter. Combine several (at least eight) samples collected from all similar areas in a clean bucket. For instance, in a yard having both high, dry areas and low, wet areas, two composite samples, one from each unique area, are required. Remove any plants or plant parts present in the sample and submit about a cup of each sample for analysis.

Soil reaction, a measure of acidity/alkalinity, is indicated by the pH results. The pH scale ranges from 0 to 14 with readings below 7 being acidic, above 7 being alkaline, and 7 being neutral. Based on the results of the pH test, amend soil to obtain a pH of 6 to 7 (slightly acidic). Slightly acidic soil reaction is desirable because it is at this pH that most soil nutrients are most available to growing plants. Add supplemental fertilizers as recommended by the soil test. It is easier to change soil before planting than after the grass is established.

Sulfur is used to make soil more acidic (that is. to lower pH). The amount to add depends on your soil type and the acidification desired. Consult the Cooperative Extension Service for help in calculating the sulfur required for your situation. Sulfur reacts slowly , so retest soil pH after 6 to 12 months to measure changes. Unfortunately, some soils resist acidification, making it virtually impossible to lower pH.

Ground agricultural limestone is used to make soil more basic (that is, to raise pH). Like sulfur, the amount to add depends on soil type and the desired change. Consult the Cooperative Extension Service for liming recommendations. To be effective, sulfur or limestone should be incorporated thoroughly into the soil by tilling. Avoid using slaked lime and burned lime because they are dangerous to handle.

Add phosphorus and potassium as recommended by your soil test. In the absence of a soil test, use 10 pounds of 10-10-10 fertilizer (or its equivalent) per 1,000 square feet to supply minimal fertility.
Amending heavy, clay soils or light, sandy soils with generous amounts of organic matter can improve the soil's drainage, aeration, and nutrient-holding capacity. If possible, apply a 2-inch layer of sphagnum peat moss, manure, compost, or some other quality organic material to your soil's surface. Use well-rotted organic matter to avoid problems with weed seeds, diseases, or other factors that can inhibit or detract from turf growth and development.

Work the amended soil to a depth of 6 to 8 inches using a rotary tiller. This operation will uniformly incorporate all amendments. After rotary tilling the soil particles should be marble sized or smaller.
Fine grade the site until it is smooth. Eliminate depressions that may collect moisture. Be sure that the slope away from buildings is 1 to 2 percent. Upon finishing this step, you are ready for seeding, sodding, or plugging your lawn.

Planting

Seeding

The seed label will provide valuable information about the grass seed. Information on the label includes the name(s) of the turfgrass species and cultivars present in the package, seed purity, seed germination percentage, crop seed content, amount of inert matter, weed seed content, lot number, and last testing date. In general, select high-quality seed of turfgrass cultivars recommended by the Cooperative Extension Service (see Turfgrass Selection). Record the seed lot number in case there are problems with the seed. This information will assist the vendor or producer to solve problems with seed should they arise.

Look for high and purity germination percentage (Table 1), fresh seed (produced the previous year), and low weed seed content (as low as possible ). Avoid buying unlabeled seed. The cost of good grass seed is a small price to pay for a high-quality lawn.

Table 1. Recommended minimum seed purity and germination percentages.

NOTE: Zoysiagrass and bermudagrass are commonly established by sodding or plugging, so they are not included in this table.

Providing enough seed to insure adequate coverage is important to seeding success, especially for grasses with a bunch growth habit (Table 2.). For lawn establishment using cool season species, provide a minimum of 10 to 20 seeds per square inch. Every seed will not produce a grass plant; a healthy, mature lawn usually averages six to eight turf plants per square inch.

Different turfgrasses have different seeding rates. These rates vary according to the size and weight of turfgrass seed. For instance, Kentucky bluegrass has a small seed and a high seed count per pound. On the other hand, perennial ryegrass has a large seed and a lower count per pound. Avoid excessive seeding rates that can produce crowded, weak, unthrifty plants and increase seedling disease invasion. In addition, excessive seeding wastes seed and money.

Table 2. Recommended turfgrass seeding rates.

After choosing the turfgrass and determining the seeding rate, be sure to distribute the seed uniformly over the planting area. Use a broadcast or drop spreader. It is advisable to apply half the seed in one direction, such as north to south, and then the other half in a different direction, such as east to west, to uniformly cover the entire area.

After the seed is in place, there are two activities that are crucial to successful turf establishment. The first is making sure there is a good seed-to-soil contact. Accomplish this task by using a lawn rake to lightly mix the seed into the upper 1/4 inch of soil.

Follow the raking with a light rolling to produce a firm seed bed. A light rolling can be accomplished by using an empty water-ballast roller. Rolling not only increases seed-to-soil contact, but firms the seedbed and slows drying of the soil.

Mulch with a thin layer of clean straw to prevent drying. Don't apply mulch heavily; you should be able to see soil beneath it. Usually 35 to 50 pounds per 1000 square feet (about 1 bale) is adequate. You do not have to remove the straw after the grass seed germinates. Grass seedlings will grow up through the light straw layer and gradually cover it as the straw decomposes. Raking off the straw would injure the young grass seedlings.

The second activity crucial to seed establishment success is to make sure adequate water is available throughout the germination process. At the time of planting, irrigate frequently and lightly, wetting the upper 1/2 inch of soil. Continue watering during the period of germination. Water less frequently, but more thoroughly and deeply, as grass seedlings mature.

Average germination times (Table 3.) vary according to the turfgrass species and the conditions under which germination takes place. Soil temperatures between 60· and 85·F for cool season grasses and 70· and 90·F for warm season grasses, along with a constantly moist seed bed, result in the quickest germination.

Table 3. Average germination time for various turfgrasses.

Sodding

If possible, choose sod grown on soils similar to the soils of the planting site or the sod may not "knit" to the soil properly and will gradually decline due to shallow rooting. Be sure to select fresh sod and plant immediately after purchase.

Sod often comes in 18-inch-wide strips that are 6 feet long. Look for sod with a thin soil layer--it will root faster and be easier to install due to its lighter weight. Most sod is harvested at a soil depth of 1/4 to 1/2 inch.

Purchase fresh, healthy sod from a reputable dealer. Plant sod in a bricklike pattern with sod edges tightly butting up to one another. Do not stretch sod--it will shrink as it dries allowing weed invasion between pieces. On slopes it may be necessary to use small wooden pegs to help keep sod in place until it roots. Under good conditions sod will begin to root within 14 days.

Using a lightweight roller, roll sod immediately after laying to insure close soil contact. Initially irrigate heavily to make sure water penetrates beneath the freshly installed sod and wets the soil. Until sod is established, continue to irrigate frequently, making sure soil is dampened to encourage root development.

Post-Planting Care

Seeded Lawns

When new seedlings have reached a height of 2 inches, they may benefit from a fertilizer application. Apply 1/2 pound of nitrogen per 1,000 square feet (if applying 10-10-10, use 5 pounds per 1,000 square feet). Water thoroughly after fertilizing. Begin mowing as turf grows using the "1/3" rule, that is, never remove more than one-third of the grass blades at any mowing. For instance, most of the cool season lawn grasses should be maintained at 2 to 3 inches. Mow these grasses when they reach 3 to 4.5 inches.

Limit heavy trafficking during the first growing season. The tender grass seedlings are subject to damage and frequently irrigated soils are easily compacted.

It may be necessary to control annual grassy weeds in spring seedings. Only one preemergence herbicide, Tupersan (siduron), can be safely applied to control these weeds at planting time. It is part of some weed and feed products containing starter fertilizer.

Postemergence broadleaf herbicide applications should not be made to new turf until it has been mowed at least three times. If portions of a lawn need to be reseeded after herbicide applications, wait at least 30 days. Be sure to read, understand, and follow the label instructions.

Sodded Lawns

Fertilize sod using a normal fertilization schedule. For instance, if you install sod in July and your normal fertilization schedule is May, June, September, and November, the first fertilization for the sod would be in September.

Mow the new sod at the desired height using the "1/3" rule: when the grass needs cutting, remove no more than one-third of the height in a single mowing.

After the sod has knit down to the soil, core aerification can help turf develop an increased number of deeper growing roots. Core aerify Kentucky bluegrass sod in the spring or fall following installation. Zoysiagrass sod can be core aerified early in the summer following planting.

Whether you establish a lawn by seed, sod, or plugs, the preparation steps are the same. Perennial weeds should be eliminated, the area should be graded, the soil should be amended and smoothed, and the best available turfgrass should be chosen for your specific needs. Then the guidelines for seeding and sodding should be followed. The final requirement is to provide adequate moisture for good establishment of the turfgrass. By establishing a healthy, vigorous turf on a properly prepared site, you will be well on your way to having an attractive lawn.