By: Darcy Larum, Landscape Designer
Ornamental grasses add height, texture, movement and color to any garden. They attract birds and butterflies in the summer, and provide food and shelter for wildlife in the winter. Ornamental grasses grow quickly and require very little maintenance. They can be used as screens or specimen plants. Most ornamental grasses are not bothered by deer, rabbit, insect pests or disease. Continue reading to learn more about cold hardy grasses for the garden.
Ornamental grasses are usually divided into two categories: cool season grasses or warm season grasses.
Growing both cool season and warm season can provide year round interest in the landscape.
Feather Reed grass – Feather Reed grass has early plumes that are 4- to 5-feet (1.2 to 1.5 m.) tall and cream colored to purple depending on variety. Karl Foerster, Overdam, Avalanche and Eldorado are popular varieties for zone 4.
Tufted Hairgrass – Generally, reaching 3-4 foot (.9-1.2 m.) tall and wide, this grass likes sun to part shade locations. Northern Lights is a popular variegated cultivar of tufted hairgrass for zone 4.
Blue Fescue – Most blue fescue is dwarf and clump forming with bluish grass blades. Elijah Blue is popular for borders, specimen plants and container accents in zone 4.
Blue Oat grass – offering tall clumps of attractive blue foliage, you can’t go wrong with blue oat grass in the garden. The variety Sapphire makes an excellent zone 4 specimen plant.
Miscanthus – Also called maiden Grass, Miscanthus is one of the most popular cold hardy grasses for the garden. Zebrinus, Morning Light, and Gracillimus are popular varieties in zone 4.
Switchgrass – Switchgrass can get 2 to 5 feet (.6 to 1.5 m.) tall and up to 3 feet wide. Shenandoah and Heavy Metal are popular varieties in zone 4.
Grama Grass – Tolerant of poor soils and cool temps, both Side Oats Grama and Blue Grama are popular in zone 4.
Little Bluestem – Little Bluestem offers blue-green foliage that turns red in fall.
Pennisetum – These small fountain grasses typically don’t get larger than 2 to 3 feet (.6 to .9 m.) tall. They may need extra protection in zone 4 winters. Hameln, Little Bunny and Burgundy Bunny are popular in zone 4.
Ornamental grasses for cold climates require little maintenance. They should be cut back to 2-4 inches (5-10 cm.) tall once a year in early spring. Cutting them back in autumn can leave them vulnerable to frost damage. Grasses provide food and shelter for birds and other wildlife in the winter. Not cutting them back in early spring can delay new growth.
If older ornamental grasses begin to die in the center or just aren’t growing as well as they used to, divide them in early spring. Certain tender ornamental grasses, like Japanese Blood grass, Japanese Forest grass and Pennisetum may need extra mulch for winter protection in zone 4.
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But I thought they were low maintenance?
In general, native grasses are low maintenance, but like any plant, they can have periodic issues that require management. This chapter covers the most common problems that can occur with native grasses.
Blue HeavenTM little bluestem in the fall. Photo by Dave Hansen.
Best Perennial Ornamental Grasses
With the popularity of ornamental grasses, new cultivars are being introduced every year. Finding one to suit your soil and climate conditions as well as visual preference should not be difficult. With recent weather extremes it is helpful to check with your trusted garden center to determine the best varieties for your region.
Blue Fescue: Festuca glauca This hardy perennial grass has been used for some time in gardens across the country. It is a cool season grass, evergreen in zone 5, hardy to zone 4, with some varieties hardy in zone 3. It is low growing, 6-10”, and very nicely mounded. Blue Fescue works nicely for containers, border edging, or in masses. Blue Fescue prefers sun to part shade and dry sandy soil. However does like supplemental water in dry spells. Does not like heavy wet soil.
Blue Oat Grass: Helictotrichon sempervirens Somewhat similar to Blue Fescue, Oat Grass is also a cool season grass, growing in upright clumps. It prefers sun to light shade and average to dry soil. Single sided seed heads develop in June, starting out white then turning golden. Evergreen in zone 5, hardy to zone 3 or 4. Also hardy up to 9,000 feet.
Feather Reed Grass: Calamagrostis x acutiflora This hardy perennial grass is cool season grass that is hardy to zone 4, where it becomes a warm season grass due to the cooler overall climate of the north. It has an upright narrow form and arching fronds, growing from 2 to 5 feet depending on variety. The flower spikes generally persist into winter. Feather Reed prefers medium to moist conditions and will tolerate heavy soils.
The‘Karl Foerster’ variety blooms earlier than most Feather Reed and works well where the growing season is short. Reaches about 4 to 5 feet in height and is hardy to zone 3. ‘Overdam’ has white variegated foliage and is best in light shade. It reaches 2 to 3 feet and is hardy to zone 4. ‘Avalanche’ is variegated, and ‘Eldorado’ has narrow green leaves that have bright gold centers.
Fountaingrass (perennial): Pennisetum alpecuroides Fountaingrass has been widely used by gardeners for some time. It is a warm season grass, that will do well in moderately moist to moist soil with full sun. It has been found to be hardy to zone 4, but general recommendation is zone 5. Winter protection is advised in case of severe cold in zone 4. Fountaingrass grows to a height of 3 or 4 feet Foliage is bright green and displays bottlebrush flowers. Excellent specimen plant or in containers.
Hakone Grass: Hakonechloa macra ‘Aureola’ A good choice for shady areas, Hakone is a hardy warm season perennial grass, to zone 4. There is a difference of opinion about whether Hakone Grass is hardy in zone 4, but this photo is from a zone 4 trial garden and it certainly looks healthy after a tough winter. Low growing at 12-20 inches, it functions well as a groundcover or in containers. It is slow growing with bright yellow foliage. Performs well in light to heavy shade in moist acidic soil. ‘Aureola’ has a cascading form supplying movement to the garden and a soft appearance. Bright variegated leaves brighten the darker corners of a shaded area.
Japanese Silvergrass: Miscanthus sinensis This particular variety of the hardy perennial, warm season grass, is 4-8 feet tall and hardy to zone 3. It’s upright stature is excellent for screening, specimen plants, large container plantings, or water features. It does very well in full sun and average to wet soils.
Miscanthus covers a large variety of grasses, and it is important that you select a reliably hardy type. ‘Silberfeder’ has wonder full plumes in fall and gets through a zone 4 winter well. It is vase shaped with silver mid rib foliage.
‘Strictus’ is hardy only to zone 5, perhaps marginally in zone 4, and grows well in full sun to part shade. Also known as porcupine grass, it has stiff leaves with yellow bands. It is very eyecatching and brightens a dark corner or complements darker plants. Some Silvergrass can be invasive and should only be grown in cultivated and tended areas rather than near natural habitats such as prairie or woodland, where it can invade unchecked.
Red Baron Japanese Blood Grass
Japanese Blood Grass: Imperata Japanese Blood Grass is a wonderful red tipped ornamental grass that develops increasingly redder as it matures each season. By autumn it is blood red. If any blades revert to green they should be removed to preserve the overall red color. It requires very little but sun to part shade with moist well drained soil. Granular fertilizer may be applied around the base of the plant about every 6 weeks, do not allow the granules to contact the foliage. Remove the foliage after the first freeze. Some of the Blood Grass spreads very aggressively, ‘Rubra’ and ‘Red Baron’ are much more controlled. Divide in spring to propagate more plants and to control size. Hardy in zones 5-9. Imperata cylindrica ‘Red Baron’ is hardy to zone 4 and is pictured here. Reaching 12-18” tall and spreading 24-35” wide, the bright green blades have red tips. Compact enough to use in small spaces or for accents.
June Grass: Koeleria macrantha June Grass is a hardy perennial to zone 3 and is tough enough to take some foot traffic. It is a small cool season grass growing to 12-18” high and is great for tough sights. It has a tight growth habit making it good for borders, along paths in both sun or shade. Showy white flower panicles appear in June, followed by straw colored seed heads. June Grass is a host for butterfly larvae. It prefers average to dry soil, and is also hardy to 11,000 feet.
Lemon Grass: Cymbopogon citratus Lemon Grass is a beautiful annual grass grown not only for its’ accent qualities, but for its’ citrus aroma and as a cooking herb. It is a bright mounded plant growing about 2 feet high. Grow it in pots and bring it indoors at the first sign of frost.
Little Blue Stem: Schizachyrium scoparium Little Blue Stem is a warm season grass that grows best in dry conditions. It is a hardy perennial to zone 4, but found to be hardy in zone 3. Clumps are green to blue-green with fluffy white seed plumes. Fall color is orange to red. Little Blue Stem does best grown in clay soil that is not wet, and tolerates light shade and drought. The University of Minnesota released a new ‘Blue Heaven’ in 2011 that should also be hardy to zone 3. Foliage is bluish with burgundy tones, and silvery white seed heads for wonderful fall color.
Pampas Grass: Cortaderia selloana ‘Pumila’ is a dwarf Pampas Grass. Pampas is an annual warm season grass, this dwarf variety growing to about 3 feet. ‘Pumila’ is more cold hardy than tender pampas grass and may be semi perennial once established up to zone 5, hardy to zone 6. Pampas is commonly grown for it’s showy fluffy white flower heads.
Pennsylvania Sedge: Carex pennsylvanica Sedge is a low growing ground cover, cool season hardy perennial grass. They generally reach about 6-12” high and are fine textured and nicely mounded. They will do well in sun or shade in average and dry soil. Sedge grass is hardy to zone 3. There are varieties that will do well in more shade, some do well in very compacted soils, more diversity every year. Blue sedge, ‘Carex flacca’, does well in some shade and is very hardy.
Prairie Dropseed: Sporobolus heterolepis Prairie Dropseed is a hardy perennial grass that is interesting throughout the growing season. It has emerald green foliage with fine textured seed heads and is gold to orang-red in fall. It is a very long living native plant with a graceful arching form of thin delicate leaves. A warm season plant, it prefers full sun and average to dry soils and is hardy to zone 3. Growing to 2 or 3 feet it is excellent for small spaces.
Purple Moorgrass: Molina caerulea A hardy perennial grass with attractive clumps of light green upright arching flower stems. Foliage turns yellow in fall and brown, yellow or purple flowers fade to tan. Purple Moorgrass is a cool to warm season grass hardy to zone 3 or 4 that self seeds. Generally midsize to tall, 5 to 7 feet. Prefers full sun and average to wet soil and does not like high alkaline soil. Mature leaves and flowers break off at the base reducing winter interest. ‘Skyracer’ has tall spires of airy heads that work well to anchor tall structures or as a finishing point of a garden. ‘Heidebraut’ is more compact at 4 feet, and ‘Moorhexe’ is compact with purple flowers.
Silver Spikegrass: Spodiopogon sibiricus A warm season grass that does well in a variety of soils and is hardy to zone 3. Silver spikegrass has a shrublike upright form that has bold dark green foliage, turning yellow orange or red in fall. It serves well as screening or a hedge and is a long term performer. It grows up to 4 feet with fine flower heads a foot above the foliage. It prefers full sun but will do fine in light shade, and average to moist soils.
Switchgrass: Panicum virgatum This hardy perennial grass prefers full sun and moderate to moist soil. It is a warm season grass. Switchgrass grows to 3 to 6 feet tall with stiff upright clumps and showy, airy flowers of pink, red or silver in midsummer. Will tolerate soil quality extremes. Hardiness varies by variety from zones 3 to 4b. Switchgrass attracts birds and does reseed. Use for screening, water gardens or prairie gardens.
‘Heavy Metal’ has been prone to rust, but ‘Northwind’ is an improved variety. It has wide bluish foliage and upright habit that can make an excellent focal point in a garden or landscape. ‘Dewey Blue’ is generally found in dry sandy coastal areas of the east and southeast, but is very hardy and does well in the midwest and even north, found to be hardy to zone 4. It grows to 4 feet tall with a graceful habit and blue foliage. Airy panicles of tan flowers appear in late summer, with seed heads that hang on through winter.
Tufted Hairgrass: Deschampsia caespitosa A cool season grass preferring moderate to moist soil but does not like clay, it is hardy to zone 3. Tufted hairgrass will need some supplemental watering. Dark green tufted foliage has airy flower panicles that change from green to yellow then nearly purple. Grows to 3 or 4 feet in full sun or light shade. ‘Northern Lights’ has cream, gold and pink vareigation and does not bloom. Also hardy to 12,000 feet.
Many gardeners have not experimented with ornamental grasses yet, here are a few of ideas for uses as well as even more varieties to consider:
Hemeln Fountain Grass Penniseturn alopecuroide
Calamagrotstis brachytrica Korean Feather Reed Grass
Muhlenbergia capillaris Pink Muhly Grass
Pennisetum 'Phoenix Magenta' Grass
Pink paintbrush grass Melinis nerviglumis 'Savannah'
I am looking for some ornamental grasses to grow in my small city lot. Can you suggest some that tolerate our clay soils and Great Lakes winters?
Ornamental grasses can add year round beauty to the flower garden and landscape. Most prefer full sun and well-drained soils. Feather reed grass, Calamagrostis x acutiflora 'Karl Foerster' tolerates clay and one of the easiest to grow. This hardy (zones 3 to 8) beauty was selected as the Perennial Plant of the Year for 2001.
Miscanthus sinensis has many varieties of varying sizes and foliage features and many are hardy zones 3 to 9. Some varieties have escaped the garden so there is concern for invasiveness. Check to see if this is a concern in your area. Avoid the aggressive silvergrass (Miscanthus sacchariflorus) that can take over your landscape.
Our native switchgrass (Panicum), hardy in zones 3 to 9 is another good choice. It does get large and rapidly spreads by seed in the garden so you may want to consider Heavy Metal, Northwind, Shenandoah, Haense Herms, Stricta or other varieties suited for smaller spaces.
Blue oat grass, Helictotrichon, zones 3 to 8 and blue fescue, Festuca (zones 3 or 4 to 8 are shorter grasses with blue foliage.
The ornamental and native sedges (Carex) and Hakone grass (Hakonechloa macra) can be a little more challenging but most do well in shady locations. Some of the sedges are hardy to zone 3 and the Hakone grass will survive zone 4 through 9.
You’ve selected a beautiful ornamental grass to add to your landscape. Now, what should you plant with it? Here are ten ideas for perfect pairings.
Think of any spot in your garden and there’s likely an ornamental grass to fit. This versatile group of plants suits all sorts of uses in landscapes, but it’s not always obvious what you should pair with them. A few details you’ll want to consider are the plants’ light and water needs, as well as their size. Perfect pairings include plants that enjoy the same growing conditions and are proportionate to one another.
Here are ten ornamental grass pairings you might consider for your own landscape.
Matching plants with similar vigor is the primary factor in this pairing. If you’re looking to fill a large space in a short amount of time, this is a beautiful and fairly inexpensive way to go.
Vertigo is an incredibly vigorous ornamental grass that can reach heights of 4-8’ with a similar girth in a single season. North of zone 8, it is grown as an annual and yes, it does get that big in one season! The photo you see here was taken near Detroit, Michigan, zone 5.
Supertunia Vista petunias are equally vigorous, with one plant growing 3-4’ across in a single season. They can easily compete with Vertigo for space in the landscape without getting swallowed up. Supertunia Vista ® Bubblegum ® is pictured here, and it also comes in four other colors that would pair beautifully with Vertigo.
Vertigo fountain grass and Supertunia Vista petunias enjoy full sun and average moisture conditions. They are both heat tolerant.
Add a bright splash of purple that lasts through fall in your landscape by combining annual purple fountain grass with cleome. We chose varieties that grow to similar heights here and interplanted them to form a tapestry of fluffy foxtail plumes and rounded flower clusters. Senorita Rosalita cleome and purple fountain grass both typically max out around 3-4’ tall.
If you’d prefer a more layered look with the cleome planted in front and the grass behind it, choose Señorita Blanca ® cleome which stays a little shorter at 18-36”.
Both of these plants will thrive in full sun with average water, and they are very heat tolerant. Since both are annuals, you’ll want to repeat this combination each year.
Cool color palettes are a welcome sight, especially in warm climates. We love how this pairing gives us the fall feels without the use of the oranges and reds typical of the season. If you garden someplace where it is still tee shirt weather in October, this might be the perfect duo for you.
Fresh green and white striped ‘Sky Rocket’ annual fountain grass is paired with the cool blue spires of Rockin’ Playin’ the Blues salvia here. Blue, green and white is a classic color combination, and interplanting them helps the colors play off one another. You’ll have blue flowers from the time of planting, with fuzzy foxtail plumes joining the party from midsummer through fall.
Both of these plants prefer full sun to light shade, average moisture, and can reach heights of 3-4’. Yes, this is a very big salvia! And if you live in zones 7 or warmer, it should return for you each year.
If blue and white is your color palette, then you’ll want to plant the Playin’ the Blues combination you saw above along with this one that features Meteor Shower verbena. Imagine both combinations running down your fence line or lining your driveway. A stunning view for such little effort!
Meteor Shower verbena is a plant that, once you grow it, you’ll want to have it in the garden every year. If you live in zone 7 or warmer, it will return on its own elsewhere you’ll need to replant. There’s something magically magnetic about its flowers. Nearly every time you pass by, you’ll find bees or butterflies there feeding. There are plenty of blooms to go around, so be sure to pick a few for fresh bouquets.
This combination will thrive in full sun to light shade with average moisture. Both plants will reach heights of about 3’.
With their native roots firmly planted in the prairies of eastern and middle America, you’ll find these two types of perennials are easily able to withstand full sun, heat, drought and less than ideal soils. Bees and butterflies are frequent visitors of coneflowers, while birds use the dried seed panicles of switch grass for nesting materials in spring.
We love how the hot red-orange to deep pink-red flowers of Lakota Fire contrast with the cool bluish foliage of ‘Totem Pole’ switch grass. Since its habit is very upright with a narrow footprint, this grass won’t overcrowd or shade out the coneflowers skirting its base. You could easily adapt this combination to work in a large or small space by adjusting the number of plants.
‘Totem Pole’ switch grass will return each year in zones 4-9 and grows 6’ tall by 2.5’ wide. Lakota Fire coneflowers are perennial in zones 4-8 and are a shorter selection, growing 12-16” tall and wide. They bloom from early summer into early fall.
Like the ‘Totem Pole’ + Lakota Fire combination above, the two perennials you see here also share native roots from the Great Plains to the East Coast. They are easy to grow in full sun and average to somewhat dry soil. Bees and butterflies enjoy the daisylike blooms of ‘Tuscan Sun’, and birds enjoy the shelter ‘Cheyenne Sky’ provides in winter.
Since both of these perennials grow about 3’ tall, plant them side by side or near enough that the golden blossoms can play off of the dark red tones in the switch grass. Both will form a dense, non-spreading clump that you can’t see through, so take care not to plant something too short behind them that will get lost.
‘Cheyenne Sky’ switch grass is perennial in zones 4-9. ‘Tuscan Sun’ false sunflowers are a bit hardier, withstanding zones 3-9. Expect the reddish tones to start developing on this grass in early summer and the golden blooms to appear from midsummer through late summer.
Prairie Winds ® ‘Apache Rose’ Panicum + Rock ‘N Grow ® ‘Pride and Joy’ Sedum
In the perennial garden, autumn flowering sedums are as iconic as garden mums in fall. The start of their bloom means fall has officially arrived. The same could be said for switch grass both come alive and show their true colors beginning in late summer and lasting well into fall.
We love how the airy panicles of ‘Apache Rose’ switch grass match the rosy pink tones of ‘Pride and Joy’ sedum. Since they bloom at the same time every year, you’ll get to enjoy this pairing for many years to come.
Grow these perennials in full sun and average to dry soils. ‘Apache Rose’ switch grass will grow 4’ tall, so you’ll want to plant the much shorter 10-12” tall ‘Pride and Joy’ sedum in front to bloom at its feet. This grass will return reliably in zones 4-9, while the sedum is a bit hardier in zones 3-9.
While many ornamental grasses can handle dry soils, fountain grass prefers consistent moisture. You’ll know it isn’t getting enough water if its leaf tips turn brown. Aronia also loves moist soils (though it can handle drier soils too). The perfect spot for this pairing would be an irrigated landscape border or slope in full sun.
We love the rich fall tones these two hardy plants offer golds, oranges, reds and purples are quintessential fall colors. But there’s another advantage of pairing these two. Early in spring, when the grass is first starting to wake up from its winter nap, the Aronia will be showing off with loads of white flower clusters which attract pollinators. Deep purple-black fruit follows in summer.
‘Desert Plains’ fountain grass is perennial in zones 5-9 and grows 3-4’ tall. Plant it behind the shorter Low Scape Mound Aronia which grows 1-2’ tall in zones 3-9.
Graceful Grasses ® ‘Fireworks’ Pennisetum + ‘Miss Violet’ Buddleia
Landscapes come alive when you add the element of movement. The fuzzy foxtail plumes of annual ‘Fireworks’ fountain grass sway in the slightest breeze while the fluttering of butterflies and pollinating bees brings movement to butterfly bush.
The rich jewel tones of variegated red fountain grass complement the purple plumes of ‘Miss Violet’ butterfly bush from midsummer into fall. We love how the arching shape of their flowers is echoed in one another. Since the butterfly bush grows a few feet taller than the grass, plant it behind or beside it. Then, skirt the grass with a white carpet of White Knight ® sweet alyssum to get this look.
Grow this combination in full sun with average moisture and well-drained soil. ‘Miss Violet’ butterfly bush will return each year in zones 5-9 and grow 4-5’ tall. You’ll need to plant the 24-30” tall variegated red fountain grass and sweet alyssum annually.
Prairie Winds ® ‘Cheyenne Sky’ Panicum + Winterberry Holly
Here’s a combination that goes the distance, delivering sumptuous red color from fall through winter in zones 4-9. ‘Cheyenne Sky’ switch grass colors up early and intensifies as the season progresses, reaching its peak when the winterberry holly turns red in fall. Though the grass will turn tan for winter, it continues to provide a beautiful backdrop for the bright red berries which persist through winter (or until the birds eat them!)
Another reason these plants make a great match is they both thrive in moist to wet soils. Switch grass is not fussy about soil it can grow in almost any conditions as long as sunshine is plentiful. But winterberry holly does not like to dry out, so make sure to plant this duo where the hose or sprinklers reach.
Winterberry holly comes in different sizes, ranging from just a few feet to 8’ tall. ‘Cheyenne Sky’ switch grass stands three feet tall. If you’d like to plant a winterberry holly along the back of the border, choose a taller variety like Berry Heavy ® or Berry Heavy ® Gold. If you’d prefer to grow these two plants side by side, choose a shorter variety like Berry Poppins ® or Little Goblin ® Red. Remember, you’ll need to plant one compatible male holly for every five females to get the berries.
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Feather reed grass, including the popular 'Karl Foerster' cultivar, needs above-average moisture conditions to thrive. Plus, unlike many other ornamental grasses, feather reed grass doesn't mind heavy clay soil that drains slowly. If you have a rain garden and want a low-maintenance, medium-height screening plant, this grass can meet your needs. It grows to about 5 feet tall with a 2-foot spread. The grass will tolerate some shade, especially from the hot afternoon sun, and it's known to attract birds. This grass prefers consistently moist soil, so regular watering often is necessary. Cut back the plant either in the fall or early spring to promote new growth.
Several exciting new ornamental grasses have come into our gardens the last few years, but none with the beauty, versatility, and reliability of feather reed grass, also known as Calamagrostis acutiflora 'Karl Foerster'.
This tall and narrow grass is believed to be a natural hybrid of C. epigejos and C. arundinacea, both natives of Europe and Asia. The noted German nurseryman, Karl Foerster, discovered the plant in the Hamburg Botanical Garden. He listed it in has 1939 nursery catalog, and included it in his 1950 garden book, The Use of Grasses and Ferns in the Garden. From there it spread around Europe until in 1964 it was brought from Denmark into the U.S.
Leaf blades are 2 to 3 feet long and a deep, shiny green. Loose, feathery flowers atop 5-foot stems appear in June and are initially light pink in color. As the seed heads mature, they become very narrow and turn a golden tan color that lasts through the fall. One of the distinguishing and highly regarded features of 'Karl Foerster' compared to other varieties is its narrow and upright growth. At only 18 inches wide and up to 5 feet tall, a grouping creates a dramatic vertical element in gardens.
The plant is fully deciduous in cold winter areas, but semi-evergreen in mild winter climates. Leaves emerge early in spring and last until early winter.
Unlike many common ornamental plants from other continents, the seeds of 'Karl Foerster' are sterile. After nearly 40 years in American gardens, it has never become an invasive pest.
Where and how to grow
'Karl Foerster' grows well in most North American gardens. Hardy throughout USDA Zones 4 through 9. 'Karl Foerster' is a cool-season grass meaning it grows best at temperatures near 70oF, and the best time to plant is spring in the North fall in the South and West. The plant does suffer in the heat and humidity of an eastern zone 9 summer.
Plant in full sun to partial shade, in well-drained soils. Moist soil and regular rain or irrigation are preferable, but the plant will tolerate heavier clay soils and drier sites.
To grow to their maximum 5-foot height, fertilizer is required. Use about 1 pound of a 10-10-10 fertilizer per 100 square feet. Low fertility is not a problem, but will result in shorter plants.
'Karl Foerster' is usually free of serious disease or insect problems although a foliar rust disease may appear in particularly wet summers and in situations with poor air circulation. Browsing deer don't bother it. Little maintenance is required except to cut back the stems to about 6 inches in late winter or early spring. In areas with mild winters the foliage may remain evergreen.
Some call the plant "metamorphic" for all the different stages it passes through in a season. Others have referred to it as the "perpetual motion grass" for its ability to catch and give motion to the slightest breeze.
Use 'Karl Foerster' as an individual specimen or small clump to provide a strong vertical accent, or mass a row to create a very fast growing, 5-foot high screen. It also serves well in containers and will survive most winters unprotected as far north as zone 6.
Naturally floral designers love 'Karl Foerster' for its use in fresh or dried arrangements. Stems cut before the flowers mature will last for months in an arrangement while maintaining the golden tan color. In heavy rain or wind the stems will dip and droop in all directions but return to vertical as soon as the storm passes.
A combination of 'Karl Foerster' feather reed grass with various other perennials makes a dramatic effect in the landscape. Consider combinations with late summer and fall-blooming perennials blooming perennials such as Coreopsis, Echinacea, Liatris, and Rudbeckia.
Given all this attributes, it's easy to see why 'Karl Foerster' feather reed grass is one of the most popular ornamental grasses year after year, and why the Perennial Plant Association named it Perennial of the Year.
Michael MacCaskey is the editorial director at National Gardening Association.