Loudoun County Master Gardeners

The Loudoun County Master Gardeners have prepared the seven plots of turf here in the Demonstration Garden to exemplify seven turf grasses that may prove suitable to local needs. Listed below are the growth characteristics of all seven, presented in three groups: (1) cool season grasses, (2) warm season grasses, and (3) grasses native to prairie states that have proven adaptable here. With this basic information, thoughtful home owners should be able to select a turf that will meet their aesthetic needs, minimize their water bills, and obviate the need for excessive fertilizer or harmful pesticides.

Fair Warning. Home owners should recognize at the outset that growing a lawn here in Northern Virginia is both difficult and expensive. The Mid-Atlantic States were covered in hardwoods centuries before colonists arrived, so no truly native grasses developed that we can cultivate today. Moreover, Northern Virginia is located climatologically in a transition zone, requiring homeowners to choose between warm weather grasses more suitable to areas further south, and cool weather grasses more suitable to areas further north. Neither is entirely satisfactory here. The dollar cost of a lawn also surprises most people. In one study, the EPA estimates $700 per year per 1000 sq ft of lawn, including installation, maintenance, and watering. That means the usual quarter-acre lot with 3000 sq ft of lawn costs over $2,000 per year, or $10,000 every five years. Given their growth problems and high dollar costs, many people are opting to reduce the size of their lawns or even eliminate them entirely.

Shown below are the three principal types of cool season grasses used in Northern Virginia.

Cool season grasses will go dormant or "brown out’” in a drought, and in the colder part of winter.

Kentucky bluegrass provides a dense, green turf. It is reported to be the most widely used cool-season grass in Northern Virginia, and is usually the most expensive. With regular mowing it makes a thick, uniform lawn, growing strongly in spring and fall, little or not at all in hot weather unless watered, and going dormant in winter when temperatures become cold. Kentucky bluegrass grows best in full sun and very poorly in shade. It needs average, well-drained soil and steady moisture. The root system is shallow and not resistant to drought. In dry conditions it goes dormant but will revive with watering. The optimum mowing height for Kentucky blue grass is three inches.

Fescue is used in cool, temperate areas such as Northern Virginia and regions to the north. With regular mowing it makes a thick, uniform lawn, growing strongly in spring and fall, little or not at all in hot weather unless watered, and going dormant in winter when temperatures become cold. Although there are about 300 species of fescue, lawn choices generally resolve into two groups, referred to simply by most gardeners as “fine” and “tall.”

· Fine Fescue includes small grasses that grow to a four or five inches in height with very fine thread-like leaves. It is drought tolerant and generally proves a good choice for shady areas, i.e., that get less than five hour of sun daily. Until the turf is mature, it tends to grow in clumps and may flop over, so is less tolerant of heavy wear than tall fescue. Its optimum mowing height is three inches.

· Tall fescue includes taller, coarser grasses with broader leaves. It is more tolerant of sun and drought conditions, and is generally the choice for play areas that get heavy wear. Most popular brand grass seed mixtures use a predominance of tall fescue. Its optimum mowing height is three inches.

Most grass seed mixtures sold in Northern Virginia blend one or more of the cool season varieties. Blending is a precaution against the rapid spread of disease among a single variety, and an effort to make the seed cover a broader range of growing conditions. The actual percentages of different types of seed should be shown on the packaging.

Warm season grasses go dormant (brown out) after the first hard frost in the fall and stay that way until April-May.

Home owners who want to reduce their water bills may want to look closely at warm season grasses.

Bermuda is grown as lawn grass primarily in warm temperate regions, such as the Sunbelt where it is valued for its drought tolerance. Propagation is by rhizomes, stolons, or seeds. In some cases it is considered to be a weed; it spreads through lawns and flower beds, where it can be difficult to kill with herbicides without damaging other grasses or plants. It is difficult to pull out because the rhizomes and stolons break readily, and then re-grow. Optimum mowing height is an inch-and-a-half.

Zoysia can tolerate wide variations in temperature, sunlight, and water, and is widely used for lawns in temperate climates. It is used on golf courses to create fairways and teeing areas. It resists disease and holds up well under traffic. It is available commercially as sod in this area, although its high cost persuades most homeowners to propagate it with plugs. It is popular because of its fine texture and soft feel, and low growth habit. It can form dense mats and even mounds that grow over low features. It generally requires less fertilization and is less prone to insect and fungus damage, depending on environmental conditions. For best appearance, turf experts recommend reel blade mowers for zoysia set to an inch-and-a-half cutting height.

Numerous native grasses are available for purchase, but generally not in typical garden centers. They are specialty items that must usually be ordered online. Master Gardeners has had little experience with them locally. The two shown in the Demonstration Garden are being grown on a trial basis.

Buffalograss is a fine-leaved native grass that has prospered on the Great Plains for centuries. It has survived severe weather extremes and has evolved into a water-efficient, sod-forming grass, which works as low-maintenance lawn grass. It greens up two-to-three weeks later than Kentucky bluegrass in spring, and stays green all summer with little or no care. It goes dormant at the first killing frost and turns a beautiful buff color until it breaks dormancy again in the spring. Unlike many native grasses, buffalograss grows quickly, as much as 5 inches within 50 days after planting. In nature, it germinates very slowly, but with a non-toxic priming of potassium nitrate to break down dormancy, germination can be accelerated to 14 days. It spreads fast on runners or stolons (like strawberry plants), but is not a pest. Each node on these stolons sends down a root, which creates another plant. This holds the runner in place. Buffalograss requires six-to-eight hours of sunlight and does especially well on hot, droughty sites where bluegrass dies out. It requires sunlight and well-drained soil and often is used for erosion control.

Blue Grama is a native warm season bunch grass with fine blue-green leaves and a short growth habit. It grows in all well drained types of soil including sandy and alkaline. It is taller than buffalograss, and more drought-tolerant. Its uses include recreation areas, roadsides, medians, cover between small tree plantings, warm season pasture, and turf. It is mixed with buffalograss for low maintenance areas with sandy or coarse soils. Blue grama is valued as forage, and for landscaping and erosion control. It is the state grass of Colorado and New Mexico.

More info on planting Blue Grama: www.highcountrygardens.com/library/view/article/323

Additional documents here: BlueGramaforLowMaintenanceLawns.pdf, PlantingaBlueGramaGrassLawnfromSeed.pdf

Note! Selecting a grass is just the first step in establishing a new lawn. Then you must plant it, cultivate it, and occasionally renew it. A lawn can become a demanding and frustrating enterprise. Loudoun County Master Gardeners* can help you through some of that. Call our Help Desk at 703 771-5150, or email us at ex107mg@vt.edu.

Grass Type