This Grass Is Always Greener . . . Except When It's Not
Weeks of dryness and accumulating heat are taking their toll on the lawn. In well-drained areas, the grass already has a sunken, sallow look to it. Six weeks of green, months ahead of brown. It's enough to drive you to zoysia grass.
Zoysia is hard to get established and entered our world as a wonder grass that was going to turn our parched suburban yards into verdant summer pastures. Named for an Austrian botanist named Karl von Zois and native to Korea, it was heavily promoted in the 1970s and 1980s as the one turf grass that wouldn't go brown in summer. Homeowners bought countless plugs that grew and spread. And spread.
The legacy of zoysia grass is a mixed one. Rarely do you find an entire lawn of it. Often it is found in patches alongside cool-season grasses, or it has invaded neighboring lawns. This is not the fault of zoysia grass, more the lack of care by the homeowner.
The grass has its enthusiastic fans. "I love zoysia grass once it's established. It has lower fertilizer needs, and weeds aren't a problem," said David Funk, who manages the University of Maryland's Paint Branch Turfgrass Research Facility in College Park.
In the heat of August, when fescue lawns need reservoir-emptying quantities of water, zoysia manages to stay short and green with a modest thirst. Its huge drawback, fans and critics know, is that come frost time in late October, the lawn will turn a morose shade of brown and stay that way until early May, right through the otherwise spectacular awakening of early spring.
Turf-type tall fescues, the predominant grass type in our region, perk up in mid- to late September and can stay looking good until the new year or longer in a mild winter. They jump back to life in March.
We live in an area turf professionals call the transition zone, meaning cool-season grasses such as fescues, bluegrass and ryegrasses suffer in the summer and warm-season grasses look awful in the cold months. Of the four main types of warm-season grasses, zoysia is the only one considered hardy enough to venture this far north. The others are Bermuda grass, St. Augustine grass and centipede grass. In arid areas of the country, people are turning to the native buffalo grass, but it doesn't do well in our humid and wet climate.
And so we are left with one awful reality about lawns in our neck of the woods: "You can have a green lawn in the summer or a green lawn in the winter, but you're going to have a brown lawn at some time," said John Ridgway, of Zoysia Farm Nurseries in Taneytown, Md. The company is one of the nation's largest suppliers of zoysia plugs, the traditional method of establishing a warm-season lawn.
He recommends spacing the zoysia plugs 12 inches apart. That would require about 5,000 plugs for a typical lawn area, at a cost of approximately $210 plus shipping. That is more than the $40 or so you would pay for a bag of high-quality fescue seed, but in the context of the work involved in installing a new lawn -- weeding, old turf removal, adding soil amendments and grading -- that cost is secondary. Zoysia is not a grass for shade or for poorly drained areas. Nor is it suited where one lawn directly adjoins someone else's, because it will invade the fescue stand.
While fescue should be cut long -- three inches -- to reduce heat stress, zoysia can be mowed at two inches or less, for a more-groomed look.
Some folks try to have the best of both worlds and overseed the zoysia with ryegrass to provide green after frost, but that is a recurring chore, Funk said.
Seed strains of zoysia have been developed, but getting the seed to germinate can be a challenge because it requires direct sunlight. This makes it difficult on a slope, where the exposed seed might wash away. The window for seeding is from mid-June to mid-July. Zoysia plugs can be planted anytime between now and late August. They need to get established before the first freeze, Ridgway said.
Zoysia lawns are typically given one application of fertilizer in late spring. Fescue lawns are normally fed in the fall and early spring.
Lee Schaber, director of technical support services for the Scotts Miracle-Gro Co., said zoysia grass is still popular in the Southeast, but he wouldn't recommend installing a zoysia lawn in the greater Washington area, where "you can get a lot of winter kill," he said. Thatch, a layer of discarded stems and roots, can build quickly and thickly in zoysia grass and harbor such lawn pests as chinch bugs, billbugs and grubs, he said.
I have not grown it because I like to see green grass in the winter as a foil to trees and shrubs that are ornamental then.
Last word to Kevin Morris, executive director of the National Turfgrass Evaluation Program, based in Beltsville: "The negative is, it's dormant here probably six months of the year. On the plus side, it's great in the summer and survives most summers here without much maintenance."