GRASS TYPES Cool Season Grass Types

Optimum air temps 65°-75°F Soil temps 55°-65°F Emerge from dormancy-rapid shoot growth, moderate root growth in spring. Intolerant of mid-summer heat stress-root and shoot

growth slows. Growth increases in the fall, moderate shoot growth

and vigorous root growth. Maintain green color well into fall.

1

Kentucky Blue Grass

QualitiesKentucky bluegrass is a cool-season grass that grows best during the fall, winter, and spring months when temperatures are cool. Its growth slows during the warm summer months. Kentucky bluegrass prefers full sun, but will tolerate some shade. When stressed by temperatures, lack of water, or poor soils, Kentucky bluegrass can be susceptible to disease and weed invasion. For a more disease resistant turf that offers good color and year-round performance, Kentucky bluegrass is often mixed with perennial ryegrass.

Identifying TipsKentucky blue grass is a dark-green, medium-textured turf. The leaf blades have a boat-shaped tip; the sides of the blades are parallel, giving a stiff appearance. This species spreads by underground rhizomes that can self-repair injured, worn, or damaged spots. Kentucky bluegrass produces a dense turf.

MaintenanceKentucky blue grass is moderate to high maintenance. It can tolerate cold winters but has a relatively low tolerance for heat and is only moderately drought tolerant. During the summer months if stressed for water, Kentucky bluegrass can go dormant. It has moderate wear tolerance, recovering quickly from some abuse.

Many times when doing a new installation of a lawn, be it at a newly built house or an existing renovation, a customer may look into the possibility of having sod installed. Very few actually go ahead with it due to the cost and that is a good thing for us as lawn care service providers. In most cases sod is one hundred percent Kentucky blue grass. I always say, “Take a picture of that sod on the day the landscaper is finished installing it because it will never look that good again.” Blue grass sod can look really nice but is extremely high maintenance and requires a great deal of fertilizer. It is also very susceptible to summer disease activity. It’s common for bluegrass sod to build up a thick layer of thatch and should be aerated at least once a year. When a customer asks if they should install a sod lawn it is usually a good idea to tell them a new lawn from seed is better.

2

Perennial Rye Grass

QualitiesPerennial ryegrass is a very competitive cool-season grass, best adapted to regions that have moderate temperatures throughout the year. It prefers full sun but will tolerate partial shade. Perennial ryegrass has the highest wear-tolerance of any cool-season grass and can tolerate high traffic. It is often used around homes, schools, and parks. Its rapid emergence helps to suppress weeds. For a more traffic and disease-resistant turf, it is often mixed with Kentucky bluegrass.

Identifying TipsRye grass is a fine-textured, rich green grass. Leaf margins are parallel, the back of the leaf is shiny and the tips of the leaf blades are tapered. Ryegrass may form clumps and has a bunchgrass-type growth habit.

MaintenanceRyegrass is moderate to high maintenance. It has a moderately low tolerance for heat, shade, and drought and a high tolerance for cold temperatures.

Ryegrass comes in many different varieties. In fact I read that there are more than two hundred different types on the market right now and each one has been developed to provide a certain characteristic be it drought resistance, color or growth habits. During the time of year that we are doing aeration and over seeding jobs we typically use a blend consisting of mainly rye grass and bluegrass. We change to mostly ryegrass, as we get closer to the colder months because most ryegrasses are very quick to germinate, even in cooler temperatures. Some varieties of ryegrass will come up in just a couple of days while bluegrass can take up to three weeks.

3

Fine Fescues

QualitiesThe fescues are true cool season grasses. The fescue species are easily seeded and include the sub species of tall bunching grasses named tall fescue and fine shorter fescues named creeping red, hard fescue, chewing and sheep fescue.

All of the fescues share the same variety characteristics with the three dominant ones being shade tolerance, staying green all year, and having good drought resistance. Fine Fescues are more cold and shade tolerant than Tall Fescue.

Identifying TipsFine fescues are a very fine-bladed grass with a deep green color. Fine fescue has two distinct growing habits: it spreads very slowly by very short rhizomes and is a bunchgrass with an upright growth habit.

MaintenanceFine fescue is very low maintenance. It does not require much fertilizer and does not need excessive amounts of water. A high mowing cut is recommended. Fine fescue has a high tolerance for cold temperatures and shade, moderate tolerance for drought and wear, and low tolerance for heat.

Occasionally you will get a customer who has done plenty of research about lawn care on the Internet. I once had a woman tell me that when we over seeded her lawn she wanted us to use one hundred percent fine fescue. The reason she had was because it reminded her of how lawns looked during the colonial period of The United States. Seldom at a loss for words I was a little bit long for a reply to her theory. I think I just agreed with her. Maybe a lawn that is one hundred percent fine fescue looks like an old colonial type home but it also builds up a great deal of thatch in sunny areas and is very quick to go dormant when it gets hot and dry. Fine fescues are best for shady areas.

4

Cool Season Grasses deserving a quick mention: Tall Fescue and Bentgrass

Turf-type tall fescue

Turf-type tall fescue is becoming a popular turf grass for homes and industrial sites. Turf-types are coarser than bluegrass, though not as thick as traditional tall fescue commonly used as pasture grasses. Tall fescue is a bunch type grass, as opposed to the rhizomatic growth of bluegrass. Newer cultivars have the same rich green color as bluegrass. Tall fescue is more drought resistant than many other lawn grasses such as bluegrass or perennial ryegrass because roots penetrate deeper into the soil. Tall fescues are also more disease resistant and wear tolerant, making them ideal for heavy foot traffic areas and athletic fields. Like bluegrass, they are considered a cool season grass, remaining green for eight to nine months out of the year.

Sometimes you will see a lawn that has a grass type in it that just looks completely out of place. Especially in summer or hot dry periods while the rest of the lawn is stunted this grass is thriving but it looks horrible. The customer is often going to place a call to you and complain about crabgrass but you will find that this grass is not crabgrass at all. This is what many old time lawn guys refer to as that “DAMMED K-31.” K-31 is a type of tall fescue that is totally resistant to heat and drought but looks absolutely awful. It is, however, the distant cousin of the new turf type tall fescues that more resemble a dark green Kentucky blue grass.

5

Bent Grass

Originally meant for golf course greens, bent grass will tolerate very low mowing, however, when grown to normal height found on most homes, it becomes shaggy. Bent Grass does not tolerate hot, dry weather, or cold winters. NOT DESIGNED FOR NORMAL HOME USE, unless your home is on a golf course green and you plan on mowing your lawn every other day at 1".

We used to have a customer in Maine who lived just off a golf course fairway. I’m not sure if that is the reason why he decided it would be a good idea to have a bent grass lawn or not but his lawn was made up of one hundred percent bent grass. Let me tell you, it looked awesome! He kept it cut at about one inch and somehow was able to keep it looking good all the time. Usually it is necessary to apply many fungicides and maintain a perfect fertilizer regimen to keep the bent grass lawn looking nice. Occasionally you will have a customer who installs a putting green at their house and wants us to take care of it. This is usually not a good idea as I recall a time when an inexperienced employee of mine many years ago applied a granular pre-emergent to a putting green in a customer’s back yard. That customer happened to be Dwight Evans, the legendary right fielder for the Red Sox. And granular pre-emergent is a bad idea for a putting green.

6

WARM SEASON GRASS TYPE Emerge from dormancy more slowly, they do not reach maximum growth rate until mid-summer. Growth rate slows in fall. Goes into dormancy in regions where soil temps go below 50°F. Lose chlorophyll as they go dormant stay green in continually warm temps.

7

St. Augustine Grass

St. Augustine grass is widely adapted to the warm, humid (subtropical) regions of the world. It is believed to be native to the coastal regions of both the Gulf of Mexico and the Mediterranean.

AdvantagesSt. Augustine grass produces a green to blue-green dense turf that is well adapted to most soils and climatic regions in the south. It has relatively good salt tolerance and certain cultivars possess good shade tolerance. Establishment of St. Augustine grass from sod is quick and easy.

DisadvantagesSt. Augustine grass, like most turfgrasses, has certain cultural and pest problems. It does not remain green during drought conditions without supplemental irrigation. It produces thatch under high fertilization and irrigation regimes. It has poor wear tolerance and will generally not stay green throughout the winter months in many parts of the state. The coarse leaf texture of most cultivars is objectionable to some people. The major insect pest of St. Augustine grass is the chinch bug, and there are currently no chinch bug resistant cultivars available. Grubs can also be a major insect pest. Some cultivars are also susceptible to diseases such as gray leaf spot, brown patch, take-all patch, and root rot. Additionally, there are no herbicides available to control hard-to-kill grass-type weeds that may become established in the turf.

The horror stories about St. Augustine Grass continue to come in on a regular basis. Typically the amount of water and nitrogen that are necessary to create healthy St. Augustine on a regular basis is to the point where many counties in the south (especially Florida) have created legislation to not only reduce fertilizer and irrigation but to actually restrict the use of St. Augustine on new construction. To create good healthy St. “Aug” you have to be on top of your game and communicate very well with your customers.

8

Zoysia

Zoysia is not as shade tolerant as St. Augustine, but is considerably more tolerant of shade than Bermuda grass. Because zoysia is the most winter-hardy of the southern grasses, it does better in the upper south regions. Zoysia is not as drought tolerant as bermuda or buffalo grass. It is most often planted as sod or plugs. Zoysia spreads by stolons and rhizomes, and considerable time is required before plugs will form a complete cover.

Zoysia grass is extremely drought tolerant. Although it does turn straw colored under severe drought conditions, it has the capacity to respond to subsequent irrigation or rainfall. Its water requirements are similar to those of Bermuda grass. The leaf blades of zoysia grass are among the first to roll under drought conditions, thus it tends to conserve moisture more effectively than other species. Zoysia grass also has a deep root system allowing it to more effectively extract water from greater soil depths.

Zoysia grass is nearly as salt tolerant as Bermuda grass. It is widely grown along sandy seashores where drainage is adequate. Zoysia grass does not tolerate poorly drained soils whether they are saline or otherwise.

Zoysia grasses are among the most wear tolerant turf grasses. However, their slow rate of growth gives them very poor recuperative potential. Therefore, they perform satisfactorily on lawns, golf course fairways and baseball fields. But, they are not recommended for football or soccer fields where traffic is concentrated in certain areas of the field. If the grass is completely worn in those areas, zoysia grass is very slow to fill in the damaged areas.

I’ve always heard lawn technicians complain about the strength it takes to push a full spreader through a healthy patch of Zoysia. It is well known for its thickness and ability to suppress weeds naturally. A small percentage of homeowners in the north have begun to use Zoysia and there is nothing stranger than to see a thick healthy lawn that is brown ten months per year.

9

Bermuda Grass

Bermuda Grass is one of the most sun loving warm season lawn and pasture grasses.  Bermuda can be easily planted from grass seed and provides a good "medium plus" turf grass lawn in Southern areas.  Bermuda turf requires a moderate amount of lawn grass care, maintenance and mowing.

This grass is a perennial sod former, dark green, drought resistant, low growing, fast repairing, full sun, has fair salt tolerance, can be mown closely, forms a dense turf,  goes into dormancy when temperatures drop below 60 degrees and greens up fast when temperatures rise. Once only grown from sod or sprigged t is now available as seed in both common and improved varieties.  Bermuda spreads by rhizomes and stolons and is a highly diversified grass.

Lawns planted in Bermuda grass can attain full lawn coverage in one year.  It is not uncommon for seeded Bermuda lawns to be established within 60-90 days.  This grass is one of the few warm season coverage that will grow a little further north in colder climates. It will turn brown at the first dip in temperature though.  Look for more cold tolerant varieties. In the more warmer tropical south, during average rainfall years, Bermuda will retain a beautiful green color all year round. This grass can be grown on low to high maintenance schedules depending upon the usage.

10

Centipede Grass

Centipede grass, Eremochloa ophiuroides (Munro) Hack, is a coarse-textured perennial grass that spreads by stolons. Centipede grass produces seed and is readily propagated by seed. It has a yellow green color and is particularly sensitive to iron deficiency.

Centipede grass forms a dense turf and has a relatively slow rate of growth. It requires less mowing than Bermuda or St. Augustine grasses and is often called lazy man's grass. Centipede grass remains green throughout the year in mild climates, but leaves and young stolons are killed during hard freezes. It does not have a true dormant state and resumes growth whenever temperatures are favorable.

Centipede grass is best adapted to sandy, acid soils where annual rainfall is in excess of 40 inches. It tolerates very low soil fertility levels and thrives on moderately fertile soils. Fertilization rates should not exceed 2 pounds of nitrogen per 1,000 sq. ft. per year on heavy soils or 3 pounds of nitrogen on sandy soils. Centipede grass is moderately shade tolerant, but grows best in full sunlight. It is not as salt tolerant as St. Augustine or Bermuda grass. Centipede grass thrives on moderately acid soils, pH 5 to 6. Above pH 7.0 iron becomes a limiting factor and supplemental applications of iron may be required.

Centipede grass does not enter a true dormant state during winter months and is severely injured by intermittent cold and warm periods during spring. Hard freezes kill the leaves and young stolons of centipede grasses and the grass recovers as soon as temperatures are favorable. When this cycle occurs several times during the winter months the grass is depleted of energy reserves and is susceptible to extreme winterkill. Thus, its adaptation is limited to areas with mild winter temperatures.

11

Winter Overseeding with Perennial Ryegrass

In the south, many homeowners use improved perennial ryegrass to overseed Bermuda grass, which keeps the lawn green through the winter. The best time to overseed in the upper south is during the first half of September. The best time in the lower south regions is the last half of September into the first part of October. Ideally, perennial ryegrass should be seeded about 6 to 8 weeks before the average date of the first heavy frost, and before the Bermuda grass goes dormant. The lowest seeding rate just to give the lawn a little green color throughout the winter is 3 lbs. per 1,000 sq. ft. However, use 8 to 10 lbs. per 1,000 sq. ft. to keep a fairly thick green lawn during the winter months.

Overseeding does not require any special equipment other than a seed or fertilizer spreader. The biggest potential down side to overseeding with perennial ryegrass is that some plants may linger as the weather turns warmer into the summer. The ryegrass then becomes weeds in the bermuda lawn. Low mowing and less water will encourage the Bermuda grass over the ryegrass, or use a post-emergent herbicide to control the ryegrass.

Southern grasses do not produce quality lawns when mixed. Since they spread by stolons, mixed varieties will tend to segregate and form distinct patches of each variety. Choose among the southern grasses that best adapt to your geographic area and particular lawn conditions, i.e. sunny, shady, humid, or arid. Next, decide if you want to use seed, sod, or sprigs. It can be a lot of work to do yourself, but a beautiful, well-maintained lawn is worth it! Your home, family, and environment will benefit.

12