The bold foliage and flowers of Chinese rhubarb (Rheum palmatum) intrigue me. Can you tell me what garden conditions it needs to thrive?
Anne Randal, Greenville, OH
The dark stems and large, textured leaves of Chinese rhubarb make a bold statement. This rhubarb is ornamental, not edible.
Photo/Illustration: Jennifer Blume
Gary Keim, a garden designer in Swarthmore, Pennsylvania, replies: Chinese rhubarb is a close relative of garden rhubarb (Rheum X hybridum), which is used to make pies. While garden rhubarb is cultivated for its edible, succulent, red stems, Chinese rhubarb is grown purely as an ornamental plant. Its dark red stems and large, textured leaves make a bold statement in the garden, and a well-grown plant can be 6 feet across. Chinese rhubarb blooms in early summer, thrusting skyward a 6-foot spike of red flowers.
A native of northwestern China, Chinese rhubarb is hardy in USDA Hardiness Zones 5 to10. It enjoys the same conditions garden rhubarb does: deep, well-drained soil, rich with organic matter, and even moisture throughout the growing season. Rhubarb is a heavy feeder, so a top dressing of well-rotted manure or compost each autumn will maintain a high level of vitality.
Since a mature specimen of Chinese rhubarb can be huge, place it accordingly to serve as a focal point or to visually anchor a bed. Site it in a location where there is protection from hot afternoon sun, otherwise the foliage may wilt. Be sure to give Chinese rhubarb adequate room to grow. Young, seed-grown plants at nurseries are often deceptively small. Look for the especially stunning cultivars ‘Atropupureum’, ‘Rubrum’, or ‘Red Select’, all of which have red-flushed leaves. R. palmatum var. tanguticum is a strong grower with beautiful, deeply lobed leaves.