Eriophorum chamissonis
Chamisso's cotton-grass
Circumboreal Northern Hemisphere wetlands
Overview
Eriophorum chamissonis is a creeping perennial sedge that grows 8-24 inches (20-60 cm) tall, spreading by underground rhizomes to form open colonies in wet ground. The narrow, grass-like leaves are 0.1 inch (2-3 mm) wide and channeled, mid-green fading to russet in autumn. In late spring and early summer each stem is topped by a single, dense, rounded head of silky bristles 1-1.5 inches (2.5-4 cm) across, opening pale and aging to a tawny, cinnamon-russet color rather than the pure white of other cotton-grasses. These cottony heads catch the light and move in the wind, persisting for several weeks before the seeds disperse. Plants establish and spread within two to three seasons where conditions suit. Eriophorum chamissonis grows in full sun to part shade in permanently wet, acidic peat or bog soil at pond margins and in rain gardens. It needs constant moisture and fails on ordinary garden soil that dries out. The spreading rhizomes can colonize a wet area and crowd smaller bog plants. Flowering is sparse in shade or where the soil is not acidic.
Native Range
Eriophorum chamissonis is native to cold and temperate wetlands across the Northern Hemisphere, including northern North America, northern Europe, and northern Asia. It grows in acidic bogs, fens, and wet tundra.Suggested Uses
Planted at pond margins, in bog gardens, and in rain gardens with permanently wet, acidic soil, spaced 12-18 inches (30-45 cm) apart. Used in drifts for the russet cottony seed heads in early summer. Grown in wet, peaty ground where few ornamental plants establish.How to Identify
Appearance
Size & Dimensions
Height8" - 2'
Width/Spread1' - 2'
Reaches mature size in approximately 3 years
Bloom Information
Detailed Descriptions
Flower Description
white aging to russetFoliage Description
mid-green turning russetGrowing Conditions
Sun Requirements
Requires 4-12 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 full sun to part shade in permanently wet, acidic soil such as peat or bog mix at a pond edge or in a rain garden. Keep the soil saturated year-round, as the plant fails if it dries out. In a garden setting it grows in a pond basket of ericaceous compost stood in shallow water to hold moisture. The rhizomes are lifted and divided in spring to propagate and to control their spread. Ordinary garden soil and alkaline conditions stunt growth and reduce flowering. The creeping rhizomes spread through wet ground and can crowd smaller plants.Pruning
Cut back the old foliage to the base in late winter before new growth begins. Spent cottony heads can be left for seed and effect or removed. No other pruning is needed.Pruning Schedule
J
F
M
A
M
J
J
A
S
O
N
D
winterearly spring
Container Growing
✓ Suitable for container growing
Minimum container size: 3 gallons