botanical name is from the Greek kalamos, a reed, and agrostis,
a grass. This highly acclaimed cultivar is one of the most
versatile, attractive, and low maintenance ornamental grasses. The
deep green, shiny foliage of this cool season grass appears in
early spring and lasts until early winter. Loose, feathery flower
inflorescences appear in June and are initially light pink in
colour. As the seed heads mature, they become very narrow with a
golden tan colour that lasts through the fall season. The growth
habit is vertical with a tuft of foliage 2-3 feet tall and flower
stems to 5 feet in height. The narrow, tight habit of this
cultivar creates a 18 inch wide clump. In mild winters the foliage
rosettes remain evergreen or may show some growth.
Grows reliably in zone 5
Full sun to partial shade
Growth is optimal in well-drained fertile soils, but this
perennial will tolerate heavy clay soils.
This clump-forming, highly ornamental grass is excellent used as a
specimen or for a vertical effect in the landscape providing a
contrast to low-mounded shrubs and perennials. Attractive hedges
or screens can be created with this five foot tall grass. It is
also useful for fresh or dried flower arrangements.
This ornamental grass provides movement in the border. The softest
breeze sets it into perpetual motion. Even in winter snows and
frost, this grass remains ornamental. Calamagrostis x
acutiflora ‘Karl Foerster’ is easy to grow and sterile
flowers eliminate any chance of this grass becoming invasive.
Plant this cool season grass in fall or spring. It tolerates a
wide range of conditions in full sun or partial shade. Growth is
best in well-drained and moist fertile soils, but it will tolerate
poorer drained soils. Space 18 inches apart. Water well until
plants are established.
Calamagrostis x acutiflora ‘Karl Foerster’ is a long-blooming,
low maintenance, long-lived perennial
grass for full sun to
partial shade. This grass grows best in well-drained fertile soils
with sufficient moisture, but will tolerate heavier clay soils and
drier sites. Fertilizer may be required to produce maximum height.
fertility will result in shorter plants. It is usually free of
serious disease or insect problems although a foliar rust disease
can occur in wet summers in situation with poor air circulation.
Little maintenance is required except to cut back the stems to
about 6 inches in late winter or early spring. Sterility
eliminates any chance of this cultivar becoming an invasive plant
or create unwanted seedlings in the garden.
Karl Foerster called Calamagrostis x acutiflora ‘Karl
Foerster’ the "metamorphic grass". Others describe it
as the "perpetual motion grass". The slightest breeze
sets this grass in motion. The graceful movement is a highlight
for any landscape. It is excellent as a specimen plant or
providing a vertical accent in the landscape. Some designers use
it for creating a fast developing screen. Others find that this
feather reed grass is useful in patio pot containers. Floral
designers appreciate this cultivar 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 colour.
In heavy rain or wind the stems will dip and droop in all
directions but return to vertical as soon as the storm passes.
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 such as
Coreopsis, Echinacea, Liatris, and Rudbeckia.
It is understandable why Calamagrostis x acutiflora ‘Karl
Foerster’ is one of the best-selling ornamental grasses year