Common Name: diarrhena
Type: Ornamental grass
Family: Poaceae
Native Range: Russia, eastern Asia
Zone: 5 to 8
Height: 2.00 to 4.00 feet
Spread: 2.00 to 4.00 feet
Bloom Time: June to July
Bloom Description: Green
Sun: Part shade to full shade
Water: Medium
Maintenance: Low
Suggested Use: Naturalize
Flower: Insignificant
Culture
Easily grown in moist, well-drained soils in part shade to full shade. Prefers moist rich soils. Naturalizes by slender, creeping rhizomes and can form dense colonies in optimum growing conditions.
Noteworthy Characteristics
Diarrhena mandshurica, commonly known as diarrhena, is a rhizomatous woodland perennial grass which grows in a clump to 2-4’ tall and as wide. It is native to forests and grassy hillsides in northeastern China, Russia, Korea and Japan. Some experts continue to identify this grass by its former name of Neomolinia mandshurica. Plants feature sterile and fertile leafy culms to 4’ tall clad with lanceolate leaves to 12” long and 1/4 to 3/4” wide. Fertile culms are topped in mid-summer by raceme-like panicles (to 8-12” long) rising above the foliage bearing insignificant greenish flowers which give way to hard, brown seed heads in fall.
Genus name comes from the Greek words dis meaning twice and arren meaning male in reference to each flower having two stamens.
Specific epithet is in reference to this grass being in part native to Manchuria (northeast China).
Problems
No serious insect or disease problems.
Uses
A tough, spreading, ornamental grass for shady areas. Mass in woodland areas, shade gardens, slopes, pond margins and naturalized areas.