Eleocharis spp.
spikerushes
Cosmopolitan (wetlands of all continents except Antarctica)
Container Friendly
Native to North America
Overview
Eleocharis spp. is a genus of about 250 species of grass-like sedges in the sedge family (Cyperaceae), known as spikerushes. Plants are mostly perennial, spreading by rhizomes to form colonies, though some are annual. The genus differs from most sedges in lacking true leaves; the green, photosynthetic stems (culms) are round, square, or flattened and rise 2 inches to 5 feet (5-150 cm) tall depending on the species, sheathed only at the base. Each culm ends in a single small spikelet of overlapping scales, brown to greenish, holding wind-pollinated flowers that ripen to tiny nutlets. Spikerushes grow in wet ground, pond and stream margins, and shallow water, and several tolerate permanent flooding. E. dulcis is grown in Asia for its edible corm, the water chestnut, while slender-stemmed species such as E. acicularis are used as aquarium and pond plants. The genus is cosmopolitan and adapts to a wide pH range. Spread by rhizomes can be vigorous, so some species colonize freely in suitable wet sites.
Native Range
Eleocharis spp. is cosmopolitan, growing in wetlands on every continent except Antarctica and across temperate and tropical zones. Many species are native to North America, where they are common in marshes, ditches, and along shorelines.Suggested Uses
Planted at pond and bog edges, in rain gardens, and in shallow water for naturalistic wetland plantings and erosion control on wet banks. Slender species are grown submerged or marginally in aquariums and water-garden containers. E. dulcis is also cultivated in flooded beds for edible water chestnuts.How to Identify
Appearance
Size & Dimensions
Height2" - 5'
Width/Spread6" - 2'
Reaches mature size in approximately 2 years
Bloom Information
Flowering occurs through summer, when the terminal spikelets ripen and shed pollen on the wind. The flowers have no petals and are inconspicuous, and seed set follows within a few weeks. In mild climates some species flower over a long season.
Detailed Descriptions
Flower Description
brown to greenishFoliage Description
greenGrowing Conditions
Sun Requirements
Requires 4-10 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 Eleocharis spp. in full sun to part shade in constantly wet soil, at pond and stream margins, or in shallow standing water up to a few inches deep. The genus tolerates a wide pH range from about 5.0 to 7.5 and is not drought tolerant, so the soil must never dry out. Plants in containers are stood in saucers of water or sunk into a pond in baskets of heavy loam. Little fertilizer is needed, as most species grow in lean wet ground. Rhizomatous species spread steadily and may need confining in a basket or pot. Few pests trouble the genus.Pruning
Old stems are cut back to the base in late winter before new growth begins. Removing ripe spikelets before they shed seed limits self-seeding into nearby wet ground. Dividing congested clumps in spring keeps colonies in bounds and renews vigor.Container Growing
✓ Suitable for container growing
Minimum container size: 1 gallons