UNDERSTANDING SEEDING AND SODDING

Lawns are established in one of two ways: either by seeding or by installing sod. The end results are identical, but how you get there varies dramatically. The big difference comes in terms of time and cost. It takes longer to establish grass from seed than by installing sod. But grass seed varieties are more extensive than what’s available with sod, and the initial cost of installation is much lower. If you are considering which option makes the most sense for your lawn, here are some things to know.

The Basics

Timing. The ideal time to seed is in the late summer and into the early fall.  At this time of year the summer stresses are just about over, there should be ample rainfall and moderate temperatures and far less competition from weeds.  The second best time for seeding is very early in the spring. The difference between spring and fall is that the weather only becomes more adverse to grass development as summer approaches and the seedlings are not given sufficient time to mature. Competition from weeds such as crabgrass can severely limit the development of the seedlings as well.

Moisture. Adequate water and fertilizer are required for both.  Newly seeded lawns require frequent light watering; sod also needs moisture to ensure that plant root systems don’t dry out before they are firmly established.

Nutrients. Newly planted grass will need to receive an application of a starter fertilizer, either before, during or directly after planting.  A starter fertilizer is a blend of fertilizer especially designed for seedling development.  Be careful using herbicides around new seedlings as they are very vulnerable.  If you feel the need to apply a crabgrass control to your newly seeded lawn, check the label to ensure it is formulated for that purpose. 

Protection. Depending on the environment, newly seeded areas may need some protection, either by roping off the area or applying a layer of light straw or landscape fabric. Some of these coverings will need to be removed as the lawn becomes established; others gradually break down on their own. Depending on the variety, grass seed may take up to 28 days to germinate.

Hydroseeding. A variation on broadcasting seed onto the surface of the soil is a procedure called hydroseeding.  This involves mixing together seed, fertilizer, lime and paper mulch in a tank full of water. This slurry is then sprayed onto topsoil using a pumping system and hoses. The advantage of this method is quick germination and soil stability.

Overseeding

Overseeding or spreading grass seed over an existing lawn will inject new life into tired and thinning grass and fill in bare areas. The process can also be used to introduce improved grass varieties.

What types of lawns need overseeding? Nearly all lawns will require overseeding, and it is not uncommon to overseed on an annual basis or at least every two years to keep new and competitive plants growing in the lawn.

How is it done? Overseeding is done by broadcast spreading or by using a slice seeder, a machine that mechanically places the seed in the soil. After the process is completed, an application of fertilizer will give both new and established grasses a boost.

Aeration helps. Aerating prior to overseeding opens up the soil and the holes left from the aerator will offer protection for the seed.

As a general rule, seeding is a better choice for filling in small bare spots in your lawn whereas sodding works best for repairing larger bare areas or for quickly growing grass in those high-visibility sections of your yard. There is indeed science behind a healthy lawn. A landscape professional can offer help guide you on the type of grass best suited for your yard.

Photo courtesy of Lawns of Dallas, Dallas, TX.