Calmagrostis   ('Karl Foerster')

(cal-ah-mah-gros' tiss)

Common name: Feather Reed Grass

Family: Poaceae (Grass)

Height x width: 4-5' x 1-2'

Growth habit: upright, columnar to slightly arching

Growth rate, longevity: moderate, long lived-- 25 years or more

Foliage: to 18-36" long and 1/2" wide, linear, flat or channelled, dull to glossy green, hairless but often rough surface (scaberulous), good tan winter interest

Flowers: dense, branched but narrow panicles, mid to late summer, stiff and erect, 2-4' tall stems with 1-2' terminal inflorescence; soft appearance, silvery bronze to pale purple- or pink-bronze, fading to cream or pale brown

Hardiness: usually listed as zones 5 or 6 to 9, but usually grows well into zone 4; AHS heat zones vary with species

Soil: moist but tolerates most, thrives in permanently damp or fertile

Light: sun

Pests and Problems: none serious

Landscape habit, uses: massed, backs or borders or background for other perennials, upright effect, winter effect, living screens, wet to damp areas, wildflower meadows, dried flowers, low maintenance; one of best cool season grasses; combines well with bee balm, joe-pye weed, helen's flower, rudbeckia, interplanted with spring daffodils

Other interest: species occur throughout northern hemisphere, often in marshland and damp woodland; some species may be invasive in warm climates and ideal conditions; name from the Greek words for reed (kalmos) and a kind of grass (agrostis)

Other culture: leave foliage and flowers for winter effect, cut back in early spring near ground

Propagation: division in mid-spring once emerged

Species: about 250 species, of which 4 are more commonly found

Cultivars: of x acutiflora
 
Cultivar height leaves flowers
'Avalanche' 4-5' white stripes on green golden, fluffy
'Karl Foerster' 4'-5' green golden, fluffy
'Overdam' 2-3' white stripes on green golden
'Stricta' (often listed syn. with 'Karl Foerster' 4' green golden

(cultivar photos courtesy Missouri botanical gardens plantfinder)


©Authored by Dr. Leonard Perry, Professor, University of Vermont as part of PSS123 course.

Return to   HGPO course | PSS123 course.