Juncus rigidusHard Rush

The Juncus rigidus, commonly known as the Hard Rush, is a stiff, rhizomatous perennial rush of saline marshes and sabkha margins from the Mediterranean across north Africa and Arabia to central Asia. It forms dense colonies of erect, cylindrical, sharply pointed grey-green culms with small brown flower clusters carried near the tip.

It is one of the few structural plants that will hold on ground that is both waterlogged and saline, which is exactly the condition around constructed wetlands, treated effluent basins and coastal sabkha edges. Designers use it for bank stabilisation, water treatment planting and native wetland character.

Specifications

• Height0.8 to 1.5 metres
• Width0.5 to 1 metre per clump, spreading steadily by rhizome
• Native toThe Mediterranean basin, north and east Africa, the Arabian Peninsula and central Asia
• FoliageStiff, erect, cylindrical grey-green culms with sharp points and no true leaf blade; evergreen
• Growth rateModerate

Conditions

• SoilAccepts saline, alkaline, silty and waterlogged soils; performs on ground that defeats almost all other perennials
• LightFull sun
• WaterHigh to moderate; a wetland species that will take standing water and saline groundwater, and only moderately drought-tolerant
• ClimateThrives in hot arid, semi-arid and coastal regions with saline groundwater

Additional Features

• FormDense upright colony of rigid cylindrical stems, reading as vertical texture rather than as a mound
• UsesConstructed wetland and treated effluent planting, sabkha and lagoon edges, bank and channel stabilisation, native wetland character
• SpacingPlant 0.5 to 0.8 metres apart for a closed colony within two seasons
• Low MaintenanceCut back old growth every few years; contain the rhizome where spread must be restricted
• Pest ResistanceFree of significant pest and disease problems
• Salt ToleranceHigh salt tolerance in both soil and standing water, one of the principal reasons for specification
• Erosion ControlThe rhizome mat binds soft saline banks and channel edges effectively
• Wildlife AttractionDense colonies give cover and nesting habitat for wetland birds and invertebrates

The Hard Rush is the plant for saline wet ground, and there is very little else that will do the job.