Can You Plant Zoysia Seeds Over Centipede Grass?

Overseeding

Overseeding is the horticultural term for scattering grass seed atop an existing lawn. The sprouting grass either provides a temporary seasonal green color while the main lawn grass is dormant, or the seedlings act to fill in the bare spots in the lawn. Because of the low maintenance needs for centipede grass lawns, and this grass's sensitivity to being improperly managed, overseeding centipede grass with any other type of grass seed is problematic.

Both centipede grass and zoysia are warm-season grasses that sprout or resume growth during the warmth of spring and summer. Overseeding the centipede grass lawn with zoysia results in a disruption to growth of the centipede grass plants, or vice versa depending on which grass type is more vigorous in the following weeks after overseeding. Neither centipede grass nor zoysia tolerates being overseeded, according to Bob Polomksi, author of "Month-by-Month Gardening in the Carolinas."

Initially, the seeds of zoysia may sprout in a sparse carpet of centipede grass during the warm months. However, if a mixture of the two exists in a lawn, the maintenance needs associated with both are not similar. One of the two grasses will falter at the sake of the other. For example, centipede grass needs less fertilization than zoysia. If you fertilize to the benefit of the zoysia grass, the centipede grass also grows faster, but chances increase for the condition known as "centipede-decline." Centipede grass also needs more potassium to overwinter well. If you fertilize and manage the mixed lawn for the centipede grass, the zoysia suffers from less water and not enough soil nutrition in midsummer.

Rather than introducing any other warm-season or cool-season grass to overseed a centipede grass lawn, change maintenance practices to improve the centipede grass's density, quality and color. Centipede grass may also be started from seed, so scattering its own seed is OK. Fertilize and water the lawn correctly; overapplication of nitrogen and improper watering are the two most common errors homeowners make in managing a centipede grass lawn. Focus proper maintenance from spring to early fall to encourage the thickest and healthiest lawn heading into the winter dormancy.