Grasses - Hardy Plant Society Mid

Feature Article
Grasses—
Grow your own Prairie
by Heidi Hesselein
Vice President of Pleasant Run Nursery
F
or much of my gardening
life, the primary garden style
I knew and loved was based on
the English Cottage Garden. The
season-long color provided by an
ever-changing mix of flowering
bulbs, perennials, and shrubs
presented all I thought I needed
in gardening beauty, and I never
lacked for plant options. Then
I started to see gardens where
grasses were incorporated into
the mix, and soon gardens began
to appear which were almost
exclusively composed of grasses.
Europeans, particularly in
Germany and the Netherlands,
have been enjoying native
American grasses in their
landscapes for a long time,
developing cultivars which make
our options even more colorful
and varied. These underused
natives have reappeared in our
homeland, in the beautiful work
done by Piet Oudolf, Wolfgang
Oehme, Kurt Bluemel, and
a number of other visionary
designers. A fruitful partnership
has developed between them and
our own renowned plantsmen like
Roy Diblik, Rick Darke, Steve
Castorani, James Brown, and
John Hoffman, to name just a few.
On the East Coast,
reproducing the environmental
conditions of Midwestern
prairies can be difficult (with
differences in moisture, and soil
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composition). Luckily, there are a
number of native grasses that do
very well in our varied conditions,
and, as a nursery producing plants
for our regional landscapes, we
are growing an ever-increasing
number of genera, species, and
cultivars. The following is a
discussion of the grasses we
particularly love.
Andropogon is a genus which
is well represented in fields,
meadows, and rights-of-way.
A. virginicus or broomsedge
(zone 5) is a 3' tall example,
with an upright year-round habit
which changes from green in the
summer to a soft orange-tan in
winter. Happiest in dry, sterile
soils, A. virginicus does not do
well in sites with significant
irrigation.
Another much bigger
Andropogon, more suitable
to the back of the garden, is
A. gerardii or big bluestem (zone
3). The 5' tall stems are sturdy,
and the turkey-foot seed heads
are silvery in the fall when
backlit by morning or afternoon
sunlight. A new cultivar, which is
particularly showy, is A. gerardii
‘Red October’. The green blades
are tipped with burgundy in
summer, and the fall color is
truly spectacular, turning a bright
scarlet red for several weeks after
the first frost.
Bouteloua gracilis ‘Blonde
Ambition’ (zone 4) is a new
introduction
of blue grama.
It is a smaller
native grass,
growing about
2' tall and
producing
fine, thin,
green blades
Bouteloua gracilis
‘Blonde Ambition’
in spring. The
crowning glory is the seed head
display, with showy horizontal
inflorescences that look like tiny
tan and straw colored feathers.
The Panicum (switchgrass)
genus is a large and showy group,
containing some of our favorite
grasses. Switchgrasses (zone 4),
are amazingly resilient, thriving
in almost any conditions except
wet soils and deep shade. Heights
of cultivars vary from 3–8', and
foliage colors vary from green to
blue to vivid burgundy on the tips
of the blades. Panicum virgatum
‘Shenandoah’ is a red-tipped
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Andropogon gerardii ‘Red October’
the fall season, past the point of
other green Panicums.
Many exciting options have
Panicum virgatum Ruby Ribbons=‘Rr1’
two grasses most commonly seen
in abandoned fields and paths.
Sorghastrum nutans or Indian
grass (zone 4) is a tall-grass
prairie staple, which provides
significant food for grassland
birds. Selections have been made
that produce 2' tall blue-green
foliage clumps, out of which rise
5' tall seed heads in late summer.
Schizachyrium scoparium ‘Carousel’
Panicum virgatum ‘Dallas Blues’
Panicum virgatum ‘Northwind’
introduction from the National
Arboretum, and from it has come
a group of increasingly lovely 3'
tall blue and burgundy cultivars
like Ruby Ribbons=‘Rr1’, ‘Hot
Rod’, and ‘Cheyenne Sky’. For
steel blue foliage, it is hard to
top ‘Dallas Blues’, a 5' tall grass
with a more open habit that has
very showy large inflorescences
(orange, mauve, and purple).
For an upright architectural
grass, ‘Heavy Metal’ (4' tall)
and ‘Northwind’ (6' tall) are
both excellent, topped by airy
tan seed heads all winter. The
tallest Panicum we have grown
is ‘Cloud Nine’, topping out at 8'.
A new introduction from North
Creek Nurseries is ‘Cape Breeze’,
a 30" tall green Panicum which
maintains its green color late into
4
come from the Schizachyrium
scoparium or little bluestem
group (zone 3). Some are 30" tall,
like Schizachyrium scoparium
‘Carousel’, while other cultivars
reach 4' tall, like ‘Standing
Ovation’, ‘Smoke Signal’ and
‘Twilight Zone’. All of them have
blue-green stems in summer and
stunning fall color in shades of
purple, red, orange, and mauve.
Schizachyrium has a delicate
upright habit in dry, sterile
sites, but is often floppy in rich
or moist soils. The seed heads
are displayed climbing up the
stems and make a gauzy silver
show when backlit by autumn
sunlight. Schizachyrium spp. and
Andropogon virginicus are the
Schizachyrium scoparium
‘Standing Ovation’
Hardy Plant Society/Mid-Atlantic Group
Sorghastrum nutans ‘Indian Steel’
These emerge in beautiful shades
of copper, maturing to chestnut
tan in fall and winter. Few sights
are more entrancing than a large
expanse of Sorgastrum blowing in
the fall and winter breezes. Two
reliably steel blue cultivars are
‘Indian Steel’ and ‘Sioux Blue’.
Sporobolus heterolepis or
prairie dropseed (zone 4) makes
a fine-textured, long-lived
clump, which requires very little
maintenance. The fine green
blades are 18" tall, and are topped
by airy, elegant 24" high seed
heads in late summer and early
fall. Besides being beautiful
(especially when backlit by sun),
the inflorescences emit a strong
and sweet fragrance, detectable
from a good distance when
planted in mass. The flowering
period is succeeded by an
impressive fall foliage display
in shades of copper and orange.
The fine textured blades and seed
heads become a light tan and
are not a significant presence in
winter.
March 2016
There are many reasons
When placed in a landscape
for incorporating native
together, the end result is
grasses into the landscape.
your own “instant prairie”,
The primary reason is that
with the subtle, yearthe plantings of natives are
round appeal of movement
critical to the survival of
and changing colors.
wildlife, especially grassland
This can be augmented
birds. Even relatively
by adding a number of
limited plantings provide
lovely and resilient native
sources of food, shelter, and
forbs* to add more vivid
nesting opportunities. Since
summer and fall color.
naturally occurring grasslands Schizachyrium scoparium ‘The Blues’ in front of Lindera Some particularly showy
glauca var. salicifolia
have largely disappeared,
additions are members of
particularly on the East Coast,
the aster, dogbane, and mint
The grasses described
it is important to supplement
families, such as Amsonia, Aster,
above all provide interest and
them with whatever landscape
Echinacea, Monarda, Rudbeckia,
beauty virtually all year. The
opportunities we can create. This maintenance needed by grasses
and Solidago. Big or small in
is particularly important in urban is really just a cutback to 6–12"
scale, a garden incorporating
and suburban settings.
grasses and companion plants has
in March, before the cycle
Besides providing wildlife
something lovely to offer all year
of new growth begins. Large
habitat, prairie grasses are
and, just as important for many
grasses, such as Panicums and
excellent vehicles for topsoil
of us, grasses have proven to be
Sorgastrum, need to be divided
retention. Their root systems
consistently deer resistant.
every three to five years in order
are extremely fibrous and deep,
to keep the clumps healthy and
making them an excellent anchor vigorous. Other than that, the
Heidi Hesselein received her B.A.
in sites that experience runoff
need for maintenance is very
in English Literature at Middlebury
events. In addition, rainwater is
small, since grasses thrive on
College in Vermont, and then worked
filtered, cleaned, and retained
neglect (no fertilizer, no extra
in two California Nurseries. She joined
significantly when it passes
Princeton Nurseries in New Jersey as
irrigation, and once a year cut
a 4th generation nurseryperson, where
through beds of grasses. And,
back). If left to themselves,
she received extensive experience
prairie grasses show excellent
grasses provide soft, flowing
growing and selling a wide range
tolerance of periodic dry
movement in the summer
of woody plants. Ultimately, she
left Princeton to start Pleasant Run
conditions, making supplemental landscape, topped by dramatic
Nursery with her husband Richard, to
irrigation unnecessary when
and beautiful seed head displays
produce garden-worthy woodies and
established.
from late summer on through
perennials for the wholesale trade.
the winter. In addition to the
Heidi continues to maintain her
attractive architectural forms
status as both a Certified Nursery
grasses provide, a number of them and Landscape Professional. She
has spoken at numerous symposia,
also provide extraordinary fall
arboreta, conferences, trade
color before they transition into
organizations, and garden clubs.
the attractive tans and buff colors Listen to Heidi speak at March Into
of winter.
Spring XX. There, she will direct our
eyes upward from grasses into the
All these grasses combine
in her talk, Smaller Trees,
well together, since their preferred canopy
Bigger Impact. (See page 1.)
growing conditions are so similar.
Ed Note: Photos provided by Lisa
They always perform best in full
Strovinsky. A full-color version of this article
sun, and look particularly striking can be found on the HPS/MAG website,
www.hardyplant.org.
when sited in front of large
shrubs or evergreens, as long as
* Herbaceous flowering plants that are not
their
light
requirements
are
met.
grasses, sedges, nor rushes.
Sporobolus heterolepis
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