Calamagrostis Acutiflora "Karl Foerster"
Height: 4-6 ft. (1.2-1.8 m)
Exposure: Sun to partial shade
Soil: Will tolerate dry sandy, clay, moist to wet soils
Hardiness: Zone 4
Bloom Time: Flowers in fall
Uses: Group Plantings, Raised Planters, Entranceways, or Perennial Borders
'Karl Foerster', a feather reed grass cultivar, is named for German nurseryman, Karl Foerster,
one of the big names in the renaissance of ornamental grasses in the garden. Foerster
introduced this grass, thought to be a natural hybrid of Calamagrostis epigejos and Calamagrostis
arundinacea, to the nursery trade in 1950. Originally, he found it growing in the Hamburg
The name Calamagrostis x acutiflora (pronounced
cal-ah-mah-gros'tiss ah-cute-i-floor' ah) is from the
Greek for reed, kalamos, and agrostis, grass.
This grass is valued for its vertical lines, ability to grow in wet soils and few if any pest or disease
problems. It is a slowly-spreading, clump-forming, cool season ornamental grass which features an
upright, slightly arching, slender clump of narrow, stiff, rich green leaves growing to 3' tall and 2' wide.
Leaves produce little fall color, eventually turning tan in winter. In June, tightly-vertical flower stalks rise
well above the foliage to 6' tall bearing narrow plumes of feathery, purplish-green flowers which turn
golden as the seeds mature in summer and eventually tan. Clumps generally provide good continuing
winter interest. 2001 Perennial Plant of the Year award.
Karl Foerster grass grows out from the center, and after a few years, you may discover a hole-in-the-donut
effect. When this happens, dig it up and divide it in spring. Replant vigorous divisions from the outer sections.
Or leave a section in the ground and dig up and divide the rest of the plant.