Planting Grass Seeds

There are many kinds of grasses used in making lawns throughout America. Grass of some kind or another eventually seeds itself in to any plowed field, and if the weeds are kept cut down, grass of sorts eventually takes over. However, much study and experimentation have been undertaken with grasses during the last decades, and here are some that are widely used to make various kinds of turf in the United States.

Northern Grasses

Kentucky bluegrass is a naturalized grass, widely adapted to many differing soil and climate conditions, and because of this is one of the most popular of all lawn grasses. It in-creases by underground stems or rhizomes, grows late in the fall after other grasses have stopped; survives best roughly north of Tenn. Bluegrass can be reproduced by plugs, sodding and seeding but the last is much the simplest.

Over 30 million lbs. of Kentucky bluegrass seed is sown annually in North America. Seeding rate is usually 2-3 lbs. per 1000 sq. ft. It grows best when temperatures are 650-80° F. Kentucky bluegrass (Poa pratensis) is largely apomictic (nonsexual), that is – most seed does not require sexual fertilization, but represents the parent plant exactly. Thus almost any bluegrass can be perpetuated as a pure line. Few “selections” are improvements over natural Kentucky bluegrass. It is cut about 2 in. high. Merion bluegrass was one of the first selections, originally found as an attractive patch on a golf course near Philadelphia. It is noted for its comparatively low growth, density, good color and resistance to leaf spot disease, but, it does have some draw-backs. It does rust, demands heavier fertilization, and because of its growth tends to thatch more quickly than most other bluegrasses.

‘Park’ is another good variety of bluegrass noteworthy for heavy seed that sprouts readily. It is the results of combining a dozen natural selections made by the University of Minnesota and contains a good Measure of genetic variability that is natural to Kentucky bluegrass.

Canadian bluegrass is sometimes used on athletic fields. It is coarser than the other bluegrasses, tolerates shades and poor soil, and is usually cut 3-4 in. high.

Rough bluegrass (Poa trivialis) sometimes called Meadow grass, does well in a moist climate or in shade. It frequently is included in mixtures sold for shady situations in cool climates. It is used only in the northern and northeastern parts of the United States.

Bent grass (Agrostis tenuis) is very fine grass for northern golf greens and special lawns. They need extra attention, most are probably native to Europe, introduced into America. Redtop (Agrostis alba), widely escaped in America, is used as a nurse grass in some seed mixtures. Bent grasses all grow well in spring and fall at temperatures less than 80° F., but are not as colorful in winter as is Kentucky bluegrass. They spread above ground by stolons that root at the joints.

Most bent grasses should be mowed twice a week. They grow best in a moist atmosphere with plenty of fertilization and are tolerant of acid soil. They are at their best on the Pacific Coast from San Francisco northward and most of the seed is produced in Ore. They are also widely used on golf-course greens and small terraces in the northeastern, north central and eastern parts of the United States. Bent grasses grow best in full sun.

Seeded varieties such as ‘Highland’ and ‘Penncross’ are planted widely in the East and West, North and mid-South. The vegetatively propagated varieties often do best in specific regions or where their special needs are recognized. ‘Washington’, ‘Arlington’ and ‘Congressional’ were selected in Washington, D.C.; ‘Old Orchard’, ‘Toronto’, ‘Cohansey’, ‘Evansville’ and ‘Springfield’, and others are of Midwestern origin.

Bent grasses should be clipped 4 in. high, too low for bluegrass and fine fescue. One pound of bent grass seed is sufficient for 1000 sq. ft. With vegetatively propagated varieties, several bushels of stolons are distributed over 1000 sq. ft. and then top dressed with soil and diligently watered.

Fine fescues are the red fescues for the northern states, where most are widely established. Chewings Fescue (F. rubra commutata) was named in Europe and for many years was cultivated in New Zealand, but is now produced in Ore. The fine fescues are more wiry inhabit, grow well under a wide variety of conditions and are most used mixed in with the seed of Kentucky bluegrass.

With fine fescue, seldom is more than 2-3 lbs. of elemental nitrogen fertilizer per 1000 sq. ft. necessary annually. In a seed mixture fescues are good insurance for the less intensively tended lawns, for they do survive in difficult locations.

Fescues grow best in the fall and can be used wherever Kentucky bluegrass grows well. Between 20 and 30 million lbs. of seed are used annually, much of it grown in Canada and imported simply as Creeping Red Fescue. Fescues are usually sown 3-4 lbs. of seed per 1000 sq. ft., generally in blends with Kentucky bluegrass, and are mowed at about 2-3 in. high. Improved selections appear much the same in most lawns, with minor biological differences. They resent too low cutting otherwise they are serviceable grasses for the northern United States.

Rye grasses are of two kinds, Domestic or Italian Rye Grass and Perennial Rye Grass. The Domestic or Italian Rye Grass is usually used as a nurse grass in mixtures with slower germinating seeds, for in cool climates it makes a quick greensward. By the time the Kentucky bluegrass appears, the Rye Grass has lived out. It has also been used in mixtures Bermuda Grass and even Centipede Grass to give a green turf in the winter, but its ability to die out suddenly after a quick freeze is disappointing and Kentucky bluegrass and some fescues are being substituted more and more in these mixtures. It is sown at about 2 lbs. per 1000 sq. ft.

Perennial Rye Grass makes a very coarse, tough turf, and can die out suddenly. Its best use is not as a lawn turf but as a green manure.

Southern Grasses

Bermuda grass is as successful over a wide series of conditions in the mid-South as is Kentucky bluegrass in the North. It is probably native of Europe and Asia, certainly Africa, and now is widely established in the southern United States. There have been literally hundreds of selections under observation at various experimental stations. In the Deep South (southern Fla., the humid Gulf Coast), Bermuda grass does passingly well but there are other grasses even better adapted there. North-ward to the Carolinas and Kan., Bermuda grass is at its best.

In warm weather, if water and fertility are adequate, Bermuda grass grows rampant. With the frosts it turns brown usually until about April (whenever warm weather comes again). Dormant Bermuda grass restrains winter weeds very little, so that there are often spots of discordant green in the brown of a Bermuda grass lawn, the reason why it is advantageous to sow other grasses (Rye Grass, Kentucky bluegrass, and fescues) in the fall so the lawn will be green all winter.

Bermuda grass increases by both runners and rhizomes. It should be mowed at least twice a week for best appearance. It is not a “low-maintenance” grass requiring more fertilizer than most species. It will not grow in the shade or under trees. Seeding the genetically mixed common form is easiest, about 2 lbs. per 1000 sq. ft. The named varieties are started asexually by plugs, sprigs or chopped stolons. The latter are scattered on the top of a prepared seedbed (1-6 bushels per 100 sq. ft.) and top dressed with soil or compost.

Carpet grass (Axonopus furcatus) is tall and coarse, used ‘in some parts of the southern United States, where better lawn grasses can not be grown. It is sight green and disease-resistant, but should be grown in a moist acid soil. It reaches 8-10 in. in height, and is sown at the rate of 24 lbs. per 1000 sq. ft. Since it has creeping rootstalks it can also be planted by sprigs or plugs. Other grasses should be mixed with it if a green color in winter is desired.

Centipede grass (Eremochloa ophiuroides) is reported an erratic grass sometimes off to a fine start, then siring down suddenly or dying out in spots for teeming trifles. It is called the “lazy man’s grass,” for under optimum conditions it grows readily and requires little care. The species was introduced from China in 1919. It is at its best on the Coastal Plain from N. Car., south to northern Fla. and west into Miss. It grows well on sandy soils or clay soils. It colors yellow easily front lack of available iron in the soil, usually a condition of alkaline soils. In general, it is one of the better grasses for lawns in the South where poor soils prevail.

It is slow in growth, needing to be mowed only every 10-20 days, and this is done at a height of about 14 in. for if let alone it grows only 3-4 in. tall. It is dense in growth and so is comparatively weed-free. The quality of a centipede grass turf is not up to that of the finer-textured Bermuda grass or Zoysia.

Centipede grass is propagated by sprigs or plugs about 6-12 in. apart or from seed. The sprigs could be 1-2 in. in the ground with most of the foliage left above ground.

St. Augustine Grass (Stenotaphrum secundatum) is supposed to be native to subtropical America. It is a fairly low creeping grass, spreading by stolons, preferring a moist climate and mucky soils. It is one of the better performing grasses near southern seashores. It is coarse and of loose texture, and so is not considered an elegant turf grass, for the leaf blades may be as much as in. wide, (although newer selections may have a much finer texture, something like Centipede grass). A distinguishing feature is a curious constriction and half twist where the blade joins the sheath. It is limited to vegetative propagation by means of sod, sprigs or plugs and these if placed even afoot apart may grow into a well-knit turf in a few months in suitable weather.

Possibly its most useful characteristic is ability to grow well in the shade, better than almost any other grass in the South. Otherwise, it is mediocre. It is one of the least expensive lawn grasses of the South. However, chinch bug infestations are proving a serious problem, and where Chlordane proves ineffective, sprays of “Trithion,” “Ethion” and “Aspon” at 7-10 lbs. per acre, “Diazinon” at 4-8 lbs. per acre are being recommended every 6-8 weeks.

Brown patch disease has proved most troublesome also and may be controlled by spraying with mercurials like “Thiram” and “Kromad” as well as PCNB, at least 2 sprayings about 14 days apart. Hence St. Augustine Grass is certainly not “low maintenance.”

Experiments have shown that fertilizing with a lb. of a complete fertilizer spring and autumn with organic nitrogen in the summer is about a minimum. It should be mowed about 2 in. high and is not tolerant of weed killers but will withstand “Atrazine.”

Current varieties include ‘Roselawn’, a tall-growing pasture variety, ‘Floratine’, a recent introduction from the University of Florida which tolerates lower mowing (than 2 in.) and is dense and finer textured than some of the others.

Bahia grass (Paspalum notatum) has been a pasture grass but is fast becoming a valued ornamental. It is used in the Deep South where it is basic in most seed mixtures. It makes an inexpensive, easily maintained lawn, not necessarily as beautiful or as fine in texture as Zoysia and improved Bermuda grasses, but nevertheless serviceable. It is native to tropical America. Selections include ‘Pensacola’, ‘Paraguay’ and ‘Argentine’.

Bahia grass can exist sporadically as far north as Tennessee, but basically it is a grass for the Deep South. It has great tolerance and can stand neglected and lacked of fertility, produces deep vigorous roots which make it one of the best southern grasses for sandy soils, withstanding droughts well. It grows well in either acid or alkaline soils, and tolerates shade. Mowing can be done with a rotary mower.

This grass spreads by horizontal stems either above or below ground, so it can be propagated by sprigs or plugs, although planting by seeds is much simpler. However, the seed does not germinate well and amounts up to 10 per 100 sq. ft. must be sown to get a good lawn started. The variety ‘Pensacola’ seems to germinate best.

The term winter grass is used in the South for lawn grasses interseeded into the permanent turf (usually Bermuda grass) to provide attractive green cover during the winter. Lawn grasses adapted to growing in cool weather are chosen. They are mostly sown as annual grasses in the fall, dying out in the hot summer, resown the following autumn.

Zoysia is best planted in spring or early summer. Seed is available only of the species Z. japonica, usually sown at 2 lbs. per 1000 sq. ft. Runners of 3 joints (sprigs) of named clones are planted with 1 joint in the soil, the other 2 above. Also plugs are planted, with spacing between them not more than 6 in. The planting must be kept moist to encourage growth which is always slow in starting, usually taking 2-3 weeks.

Zoysia has been given tremendous publicity during the past to years. Actually, Z. japonica has been grown in the United States since 1906 when it was first introduced from the Orient. Now there are many varieties, all to be propagated vegetatively, all “warm-season” grasses that turn brown in winter and hence are less satisfactory than cool-weather grasses in the North (which remain green much longer). However, in the South, Zoysia grasses have their troubles also. The ‘Meyer’ variety discolors in winter more readily than some local types. Zoysia grasses do have diseases and insect pests (especially the billbug in Fla.) which are beginning to preclude its widespread use in some areas. Also a heavy-duty mower, which is expensive, is needed to mow Zoysia satisfactorily.

Nevertheless, among the Zoysia grasses are some of the finest lawn grasses for the South. They wear better than Bermuda grass, although they will not grow as fast. They withstand shade, and require but little fertilizer.

Zoysia spreads by above-ground runners or stolons, and by underground runners or rhizomes. It needs from 1-3 years to establish a sod. Once established its slow growth becomes a virtue. Mowing need be only every to days or so, and no grass makes a thicker carpet of foliage. It should be mowed at a height of 1-2 in.

Z. matrella or Manila grass grows 3-4 in. high, forms a rug like turf and grows well in many soils, in sun or shade. It stays green long at high temperatures and is resistant to most pests and even to weed encroachment. ‘Emerald Zoysia’ is similar but is faster in growth and is slightly more resistant to frost.

Z. japonica is coarser than Z. matrella and slower growing. They do turn brown in winter, but are drought-resistant. For those living in the North, who wish the lawns to be green as long as possible in the fall and winter, Zoysia should not be selected.