Spiny rush is a clumping perennial rush native to coastal and desert areas of southern California and Baja California. It grows 2-4 feet tall and 3-5 feet wide, with stiff cylindrical leaves that have sharp tips. It blooms from March to May with small, wind-pollinated flowers. Spiny rush is suitable for moist areas in gardens and helps control algae in ponds. It provides habitat for birds and can be used for erosion control on slopes.

1. Spiny (Leopold’s) Rush – Juncus acutus ssp. leopoldii
(JUN-kus uh-CUTE-us lee-oh-POLD- ee-eye)
Family: Juncaceae (Rush Family)
Native to: Coasts and deserts of S. CA, AZ, Baja. Locally native to South Bay; moist saline places,
coastal salt marshes, alkali seeps, alkali sinks at elevations < 1000 ft. Rare in wilds (habitat loss).
Growth characteristics: clumping perennial rush mature height: 2-4 ft. mature width: 3-5 ft.
Clumping or spreading, ever-green with regular water – fall dry with less. Fast growing. Stiff
cylindrical leaves have very sharp tips. Nice mounded shape at maturity – typical for rushes. Slowly
spreads via rhizomes.
Blooms/fruits: Blooms March to May or June. Flowers small, wind-pollinated, typical for the
rushes. Seed pods spherical, dark brown at maturity and quite attractive. Seeds spread by water.
Uses in the garden: Good for moist places in the garden: in rain gardens, dry swales and infiltration
basins, around ponds and pools. Interesting foliage is good choice for the mid-ground, (contrasts
well with background and fore-ground plants). Elegant in a large container. Makes a good barrier
plant! Be sure to place where sharp leaf tips will not be a problem. Soil binder - useful on slopes.
Important basketry plant wherever it grows. Also inhibits growth of algae in ponds, standing water.
Sensible substitute for: Non-native grasses like Pampas grass or non-native pond plants.
Attracts: Good bird habitat: provides cover and seeds for food.
Requirements:
Element Requirement
Sun Full sun to part-shade
Soil Very adaptable. Any local soil from sandy to clay. Takes alkali, sandy soils.
Water Best with regular to semi-regular water (Water Zone 2 to 3) even standing water,
but can take less.
Fertilizer None needed except in containers.
Other
Management: Prune off dead leaves in winter. Cut down to several inches to rejuvenate.
Contain to keep from spreading.
Propagation: from seed: easy with fresh seed; surface sow by divisions: easy in winter/spring
Plant/seed sources (see list for source numbers): 3, 8, 10, 13, 14, 16, 24 12/23/14
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