Xanthorhiza simplicissima
shrub yellowroot
Overview
Xanthorhiza simplicissima is a low, suckering deciduous shrub that spreads by rhizomes to form colonies 1 to 2 feet (30 to 60 cm) tall and indefinitely wide. The pinnately compound leaves, clustered toward the stem tips, carry 3 to 5 toothed, celery-like leaflets and emerge bright green. In early spring, before or as the leaves expand, drooping panicles 2 to 4 inches (5 to 10 cm) long bear many small star-shaped flowers in brownish-purple. The inner bark and roots are bright yellow and have served as a natural dye source. Through autumn the foliage shifts to yellow, orange, and purple before dropping. The colony grows densely enough to suppress weeds on shaded slopes and streambanks. Native to moist woodland of the eastern United States, it tolerates deep shade and seasonally wet ground. It depends on steady soil moisture and browns at the leaf margins in dry, sunny exposures. Spread by underground stems is continuous and can extend beyond its intended area over time, so it suits naturalistic plantings more than tight formal beds.
Native Range
Native to the eastern United States, from New York and Pennsylvania south to Florida and west to Texas. It grows in moist woods, along streambanks, and on shaded slopes.Suggested Uses
Used as a deciduous groundcover for shade, on streambanks, and on slopes for erosion control. It forms colonies in rain gardens and moist woodland edges. The early flowers supply pollen for emerging native bees.How to Identify
Appearance
Size & Dimensions
Height1' - 2'
Width/Spread2' - 3'
Bloom Information
Flowering takes place in early spring, generally March through April, as the new leaves emerge. Drooping panicles carry many small brownish-purple, star-shaped flowers about 0.25 inch (6 mm) across. Bloom lasts roughly 2 to 3 weeks. Small dry follicles follow in summer.
Detailed Descriptions
Foliage Description
greenGrowing Conditions
Sun Requirements
Requires 2-6 hours of direct sunlight daily
• Full Sun: 6+ hours of direct sunlight
• Partial Shade: 3-6 hours of direct sunlight
• Full Shade: Less than 3 hours of direct sunlight
Care & Maintenance
Care Guide
Grow in part shade to full shade in moist, humus-rich soil. Xanthorhiza simplicissima accepts loam, clay, or silty soils with a pH of 5.0 to 6.5 and tolerates seasonally wet ground. Keep the soil consistently moist, since the leaf margins brown in dry, exposed sites. It is cold hardy in USDA zones 3 through 9. The plant spreads by rhizomes, so a defined bed edge or barrier limits its reach. Little fertilizer is needed in woodland soils.Pruning
Prune in late winter to remove dead or weak stems before new growth begins. Mowing or cutting the colony low every few years renews dense, even cover. Unwanted runners can be dug out at the colony edge. No routine shaping is needed.Pruning Schedule
J
F
M
A
M
J
J
A
S
O
N
D
winter