Download Northern Sea Oats (Chasmanthium latifolium) in a part shade garden.

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Ornamental Grasses
Ornamental grasses are valued in home landscapes
for their hardiness and easy care, dramatic
appearance and the wide variety of colors, textures
and sizes available.
Ornamental grasses, like lawn grasses, are also
classed as cool or warm-season. Cool season
grasses begin new growth in fall or winter and
bloom in spring or early summer, but go dormant or
decline in appearance during the summer heat. Most
ornamental grasses for the South are warm season
growers. They grow rapidly during spring and
summer, bloom in late summer or fall and are
dormant through the winter.
Height
Ornamental grasses vary in height from giant reed
and pampas grasses reaching up to 15 feet tall, to
very low growing grasses used as ground covers.
Grass forms vary from low mounds to fountains and
tall verticals.
Pampas grass, one of the toughest grasses for the South.
Karen Russ, ©2007 HGIC, Clemson Extension
Types of Grasses
Ornamental grasses refers to both true grasses and
plants that have a grass-like appearance - such as
sedges - that are used for similar purposes in
gardens.
Most ornamental grasses are perennials, living for
two or more years. Annual grasses live for only one
growing season, either because of their natural
growth or because they are not hardy in our climate.
Grasses can be classed as clumping or spreading.
Spreading grasses expand rapidly by aboveground
or underground stems. Care must be used in siting
spreading grasses, or they may become invasive.
Clumping or bunch grasses grow in a clump that
gradually increases in diameter.
Ornamental Features
The flower heads of many grasses are very showy.
Flowers vary in size, color and texture from the airy
clusters of tiny purple flowers that float above
purple muhly grass to the huge feather dusters of
pampas grass. Flowers and seed heads last for
weeks or months, many providing interest through
the winter.
Foliage provides additional interest with a range of
fine to coarse texture, softly arching or firmly
upright form and deep green, blue, red or purple,
yellow and variegated leaf color. Many grasses have
good fall color, changing to yellow, orange, red or
purple before fading to tan or straw for winter.
Some cool season grasses are evergreen.
Grasses also give interest to the garden in ways that
few other plants can. They sway easily in the wind,
adding the appeal of movement and rustling sound
to the landscape. Their rapid growth and changing
appearance through the year adds seasonal interest.
Landscape Use
Maintenance
Because grasses are such a varied group, they can
be used for many different landscape purposes. Tall
grasses can be used as quick growing screens or
hedges. Grasses with striking form, color or flowers
can be used as accent plants. Grasses can be used in
place of shrubs, in perennial borders and container
plantings. They can be used as groundcovers, for
erosion control and as edgings. The flowers can be
used for fresh or dried arrangements.
Watering: Once established, moisture needs vary
by grass species, soil type, temperature and other
factors. Most ornamental grasses will grow best
with at least 1 inch of water per week from rain or
irrigation. Drip irrigation is an excellent way to
water grasses. It saves water by applying water
directly to the roots where it is needed, and reduces
the chance of foliar diseases.
Growing Conditions
Grasses are a large group, with varying needs, but
some growing preferences are shared by nearly all.
Most ornamental grasses must have well drained
soil. Raised beds can be used to ensure good
drainage. Ordinary garden soil is adequate for most
grasses. Some grass-like sedges and rushes will
thrive in moist or even wet soil.
Most ornamental grasses need full sun. Some
exceptions are northern oat grass, Japanese forest
grass, and sedges. Many cool season grasses which
require full sun farther north, will prefer some shade
during the hottest part of the day in the South.
Planting
While many perennials prefer fall planting in South
Carolina, the warm season ornamental grasses will
do best if planted in spring. Cool season grasses can
be planted in fall. Plant grasses as far apart as they
will grow in height at maturity.
Ornamental grasses are usually available grown in
containers. If plants are pot-bound, loosen the roots
around the bottom and sides of the root ball. Dig the
planting hole at least twice as wide as deep. Spread
the roots out and refill the planting hole, firming the
soil in around the plants roots to avoid air pockets.
Be sure the crown of the plant (the point where
roots and top join) is even with the soil surface.
Water plants thoroughly after planting to settle the
soil around the roots. Pay close attention to
watering the first few weeks after planting. While
many mature grasses are drought tolerant, they must
have a well-established root system to withstand dry
periods.
Fertilization: Most ornamental grasses need very
little fertilizer. It is best to base any fertilizer
applications on the results of a soil test. Excessive
nitrogen in the soil can lead to disease
susceptibility, rank growth, and weak stems.
Cutting Back: Cut back grasses before the new
seasons growth starts. Since many grasses are
attractive in the garden during winter, cutting back
can be done in late winter or early spring. Cut stems
to a few inches above ground level for best
appearance. Grasses can be cut by hand with
pruners or hedge shears, with electric hedge shears,
or a weed eater with a brush-cutting blade.
Some evergreen grasses do not recover quickly
from cutting back. Comb the foliage of these
grasses with gloved hands in spring to remove old
leaves.
Dividing: Most grasses should be divided every 3
to 4 years. If ornamental grasses are not divided,
they eventually become thin or die out in the center.
It is best to divide grasses while they are a
manageable size. Overgrown grasses can be
incredibly difficult to dig and divide.
Dig and divide warm season grasses during early
spring, just before new growth starts. Divide cool
season grasses in early fall.
Most grasses have very tough, vigorous root
systems and may have to be divided with a shovel,
saw or ax. Hose off soil to make the roots easier to
work with. Separate and replant the vigorous
growth on the outer edges of the clump. Replant
promptly, never letting the roots dry out. More
information on division can be found in HGIC
1150, Dividing Perennials.
Staking: Some tall grasses look best when staked to
prevent them from bending or falling over during
wind and rain. Reduce the need for staking through
variety selection, proper spacing, well-timed
division, and avoiding excessive fertilization or
water.
Problems
Ornamental grasses have few insect or disease
problems. Rust occasionally attacks some cool
season grasses, but most plants recover quickly after
being cut back. Anthracnose is occasionally a
problem. Diseases are most common on plants in
improper growing conditions, with low light, poor
air circulation or excessive fertilization.
A few grasses can themselves become pests if
planted in the wrong location. Be cautious in siting
running grasses or confine the root system in a deep
bottomless container. Non-native grasses that seed
vigorously should be used with care, especially near
natural or wetland areas.
Species & Cultivars
•
'Variegata' has leaves brightly striped with
creamy yellow in spring. The leaves fade
somewhat by fall. Grows 6 to 12 feet tall.
Korean Feather Reed Grass (Calamagrostis
brachytricha): Arching dark leaves form a broad,
mounded clump 2½ feet tall covered by tall pink
plumes in fall. This species tolerates hot summers
better than C. acutiflora. It will grow best in the
South in light or part shade, and moist well-drained
soil.
Feather Reed Grass (Calamagrostis x acutiflora):
This cool season clump forming evergreen grass
grows best in the upper Piedmont. It grows
narrowly upright 2 to 4 feet tall with slim, tall
flower heads in spring that turn golden tan in
summer. Sun or part shade.
• 'Karl Foerster' is strongly upright and early
blooming.
• 'Stricta' is strongly upright.
• 'Overdam' has white striped foliage turning
pink in cool weather. This variety must have
part shade and moist soil.
Japanese Sweet Flag (Acorus gramineus): Fine
grass-like, foot tall semi-evergreen leaves give a
texture similar to mondo grass, but thrive in
constantly moist, even wet soil. They will also grow
in ordinary garden soil in part shade, but need more
moisture in full sun.
• 'Licorice' has evergreen licorice scented
leaves.
• 'Ogon' has yellow leaves that are especially
bright in spring and fall, with best color in
part shade or shade.
Big Bluestem (Andropogon gerardii): This very
tall native grass grows from 3 to 8 feet tall in a
narrow clump. The leaves are blue-green in
summer, turning rust in fall. It needs full sun and
prefers moist to average soil but is very drought
tolerant once established.
Giant Reed (Arundo donax): One of the largest
grasses, giant reed grows 10 to 20 feet tall. Wide
blue-green semi-evergreen to evergreen leaves are
arranged along bamboo like stems. Large flower
plumes appear in late fall. It can be invasive. It
prefers sun and moist well-drained soil, but tolerates
wet soil.
'Karl Foerster' Feather Reed Grass with mature seed heads.
Karen Russ, ©2007 HGIC, Clemson Extension
Japanese Sedge (Carex morrowii): This grass-like
plant is grown for its foot tall slender leaves. It
grows best in part shade or shade, and moist or wet
soil.
• 'Goldband' is evergreen, with stiff brightly
striped white and green leaves.
• 'Silk Tassel' forms a wide spreading clump of
frosted looking thread-like foliage.
Weeping Sedge (Carex pendula): Wide, weeping
evergreen leaves form a wide, bright green mound 2
to 2 ½ feet tall. Grows best in part shade or shade in
moist, rich soil. Reseeds moderately.
Northern Sea Oats (Chasmanthium latifolium):
This native grass thrives in shade. It bears oval
flowers prized for dried flower arrangements
dangling from 3-foot tall curving stems in fall.
Grow in shade or part shade. Prefers moist, rich
soil, but tolerates drought once established. Selfseeds abundantly. It is also called upland river oats.
Northern Sea Oats (Chasmanthium latifolium) in a part shade
garden.
Joey Williamson, ©2014 HGIC, Clemson Extension
Pampas Grass (Cortaderia selloana): Very large,
tough clumps grow up to 12 feet tall depending on
variety and soil moisture. Wide arching leaves with
sharp edges spread in a fountain shape topped by
dramatic 2 to 3 foot tall flower plumes on long
stems in late summer and early fall. Pampas prefers
full sun and well-drained soil. It spreads slowly by
thick rhizomes to form a huge clump.
• 'Gold Band' has bright gold edged leaves on a
clump only 4 feet tall. Grown mainly for its
foliage, as its flowering is sparse.
• 'Pumila' grows to only 4 feet tall with narrow
blue green foliage. The flower plumes are tan,
standing 2 ' above the foliage. 'Pumila' is the
hardiest pampas grass variety.
• 'Silver Comet' grows 3 to 4 foot tall with
narrow white edged leaves. Plumes rise to
only 5 feet.
Weeping Love Grass (Eragrostis curvula): This
drought tolerant grass is commonly used for erosion
control on highways, but is also very ornamental.
Dark green, very fine textured foliage forms dense
weeping clumps 1 foot tall and 2 to 3 feet wide. Full
sun.
Fescue (Festuca ovina): Fine evergreen foliage
forms a low rounded tuft 12 inches tall. This cool
season grass grows best in the upper Piedmont in
sun or part shade. Well-drained soil. Comb out dead
leaves with gloves.
• 'Elijah Blue' has thread-like, powder blue
leaves.
Japanese Silver Grass (Miscanthus sinensis): The
species may grow up to 10 feet tall, with large
whisk-like flower plumes ranging in color from
reddish purple to silver. Prefers full sun and moist,
rich, well drained soil, but will tolerate some
drought once established. It often reseeds and can
be invasive near natural areas. Avoid planting the
straight species, which is most likely to be invasive.
• 'Adagio' is one of the smallest cultivars,
growing to only 36 inches tall in a tight
mound of fine green foliage. Abundant
flowering in late summer
• 'Cabaret' has centrally white-striped, wide
leaves on a strong, self-supporting 6 foot tall
plant. Purplish flower heads in early fall
mature to tan.
Bold white stripes on ‘Cosmopolitan’ Miscanthus leaves.
Karen Russ, ©2007 HGIC, Clemson Extension
•
•
'Cosmopolitan' has white striping on the
edges of its wide leaves. Strong, non-floppy
habit.
'Gracillimus' has narrow leaves with a silver
midrib, Five to 6 feet tall plants tend to flop
unless staked. Good orange to buff fall color.
•
'Rotstrahlbusch' is similar to 'Shenandoah'
with a somewhat more upright form, and is a
bit smaller and narrower.
Slender leafed ‘Morning Light’ Miscanthus
Karen Russ, ©2007 HGIC, Clemson Extension
•
•
•
•
'Morning Light' is a strongly upright plant to
4 feet tall. The slender leaves appear silvery
gray green due to fine white striping. Flower
plumes are red on opening, fading to soft tan.
'Purpurascens' grows in a tight, upright clump
3 to 4 feet tall. The leaves are green with a red
tint, turning brilliant red orange in fall. This
variety performs best in the Piedmont.
'Strictus' (Porcupine Grass) is an improved,
strongly upright form of zebra grass, growing
to 6 feet tall. It also has bright yellow,
horizontal bands across the leaf.
'Variegatus' has 5 foot tall brightly white
striped foliage. This variety will have best
color if planted in light shade. It needs to be
staked for best appearance.
Switchgrass (Panicum virgatum): This beautiful
native grass has many varieties with showy flowers,
excellent fall color and winter interest. Switch grass
refers full sun in moist to wet soil, but is highly
adaptable. It reseeds occasionally, but not
invasively.
• 'Cloud Nine' has light blue foliage growing 6
feet tall with large airy flower heads rising
another 1 to 2 feet in mid to late summer.
• 'Heavy Metal' has a strongly upright, narrow
habit with airy flowers and 3 to 4 feet tall
metallic blue foliage that turns yellow in fall.
• 'Shenandoah' has deep green leaves tipped
with purple in summer, turning burgundy
purple in fall. Flowers are reddish pink. This
variety grows to only 3 to 4 feet tall. This and
the following cultivar are excellent substitutes
for the invasive Japanese blood grass, a type
of cogongrass.
‘Rotstrahlbusch’ Switchgrass summer leaf color.
Karen Russ, ©2007 HGIC, Clemson Extension
Hairgrass (Muhlenbergia capillaris): Clouds of
tiny flowers form a pinkish-purple haze appearing
in October and fading to tan through the winter on
this showy native grass. Clumps of very fine, bluegreen to gray-green foliage rise to 2 to 3 feet tall.
Full sun, extremely drought tolerant once
established.
Hairgrass in full fall flower color.
Karen Russ, ©2007 HGIC, Clemson Extension
Bamboo Muhly (Muhlenbergia dumosa): Arching
bamboo like stems with billowy light green foliage,
grow 5 to 6 feet tall. Bamboo muhly is an excellent
non-invasive substitute for bamboo. Full sun,
drought resistant once established.
Fountain Grass (Pennisetum alopecuroides):
Beautiful, cream to pink, bottle brush shaped flower
heads appear from mid to late summer above fine,
arching mounded foliage 3 to 4 feet tall. Prefers sun
and moist but well drained soil. Fountain grass
reseeds and may be invasive into natural areas.
• 'Hameln' is compact, growing to only 2 feet
tall. Performs best in the Piedmont.
• 'Little Bunny' grows to only 1 foot tall.
• 'Moudry' has striking black flower spikes in
late summer to early fall. It grows 2 to 3 feet
tall. This variety reseeds abundantly.
•
'Sioux Blue' has stiff, upright blue-gray
foliage.
Chinese Fountain Grass (Pennisetum orientale):
Soft pink or white flower spikes appear from late
spring through fall above blue green foliage only
1½ feet tall. It spreads slowly by rhizomes, but
rarely reseeds.
Annual Fountain Grass (Pennisetum setaceum):
While it must be grown as an annual throughout
South Carolina, it grows 4 to 5 feet tall by summers
end. Striking purplish pink flowers above slender
green foliage are produced continuously through
summer. Prefers sun and moist, well-drained, fertile
soil.
• 'Rubrum' (Red Fountain Grass) has dark
burgundy-red foliage and bloom spikes.
• 'Rubrum Compacta' grows 2½ to 3 feet tall,
with even finer foliage, but is not quite as red.
• 'Burgundy Giant' is a hybrid with very broad,
deep red foliage and maroon flower spikes. It
is robust and grows 5 to 6 feet tall.
Little Bluestem (Schizachyrium scoparium): This
native grass, also called broom sedge, grows to 3
feet tall, with fluffy flower spikes in mid fall held
well through the winter. Upright, light green foliage
turns orange tan in fall. Prefers full sun and tolerates
almost any soil.
• 'The Blues' has very blue leaves to only 1½
feet tall. It has very bright orange fall color.
Indian Grass (Sorghastrum nutans): This
adaptable tall, upright native grass blooms with
narrow, dark gold flower plumes in late summer.
Foliage turns golden tan in the fall. Prefers full sun
and rich, moist well drained soil, but tolerates most
soil. Plants reseed, but are not invasive. Indian grass
is the state native grass of South Carolina.
Indian grass (Sorghastrum nutans) along a sunny roadside.
Joey Williamson, ©2014 HGIC, Clemson Extension
Prairie Dropseed (Sporobolus heterolepis): Very
fine-textured leaves arch to form a wide clump 2
feet tall. Filmy flowers appear in late summer, well
above the leaves. Prefers full sun and well drained
soil. Very heat and drought tolerant once
established.
Giant Needle Grass (Stipa gigantea): The flower
stems are very tall, arching and airy, with gold
dangling flowers in early to mid summer. Narrow
evergreen foliage grows 2 tall. Prefers sun with
moist, well drained soil.
Texas Needle Grass (Stipa tenuissima):
Exceptionally fine textured evergreen leaves grow
in a weeping mound. Fine billowing flower spikes
appear in summer. Prefers sun and dry soil, avoid
excessive water once established
Sea Oats (Uniola paniculata): This major native
Southern beach grass tolerates harsh growing
conditions and stabilizes dunes. Gray-green sharp
leaves grow 3 to 8 feet tall topped by arching flower
stems. Prefers full sun and well drained sandy soil.
Do not fertilize sea oats. Never collect or purchase
wild collected plants.
Prepared by Karen Russ, HGIC Horticulture Specialist & Bob Polomski Extension Consumer Horticulturist, Clemson University. (Revised
11/04. Images added 09/07 & 11/14.)
This information is supplied with the understanding that no discrimination is intended and no endorsement of brand names or registered
trademarks by the Clemson University Cooperative Extension Service is implied, nor is any discrimination intended by the exclusion of products
or manufacturers not named. All recommendations are for South Carolina conditions and may not apply to other areas. Use pesticides only
according to the directions on the label. All recommendations for pesticide use are for South Carolina only and were legal at the time of
publication, but the status of registration and use patterns are subject to change by action of state and federal regulatory agencies. Follow all
directions, precautions and restrictions that are listed.
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