1 named cultivar

‘Shara’River Mat Rush

grass

River Mat-rush

Lomandra fluviatilis

The Story

Plant Bio

Lomandra fluviatilis, commonly known as river mat-rush, is an evergreen perennial grass native to eastern Australia that forms dense, fine-textured tufts of narrow, arching foliage. The slender, channeled leaves have a distinctive blue-grey to grey-green coloration and terminate in small two- or three-toothed tips.

This species is distinguished from other mat-rushes by its riverine origin, which grants it superior tolerance to high humidity and seasonally wet soils. In spring and summer, it produces branched clusters of small, cream-to-yellow flowers with prominent pointed bracts held among the foliage.

Uses & Benefits:

Provides a fine-textured, arching, blue-grey architectural element that softens hardscapes and retains color year-round.

Highly drought-tolerant once established and requires minimal maintenance, making it ideal for low-input landscapes.

Stabilizes soil along slopes and swales while offering shelter for beneficial ground-dwelling insects.

Essentials

At a Glance

Plant Type

Grass

Height

24"

Width

24"

Light

Full Sun, Partial Sun

Zones

8, 9, 10

Water

Low to Moderate

Humidity

High

Lifespan

Perennial

Native To

Australia

Toxicity

Non-toxic

Planting

How to Grow

Select a planting site in full sun to light shade with well-drained to moderately moist soil.
Dig a hole twice the width of the root ball and set the plant so the crown sits level with the surrounding soil.
Water deeply and regularly during the first growing season to establish a deep, drought-tolerant root system.
Apply a thin layer of organic mulch around the base, keeping it clear of the crown to prevent moisture retention.

Pro Tip

Avoid shearing the foliage into the lower woody stems, as this prevents clean recovery. Instead, rejuvenate ragged clumps by cutting the entire plant back to about six inches above the ground every three to five years in early spring.

Keep It Thriving

Care Guide

Do

Water occasionally during prolonged dry spells to maintain the lushest foliage appearance.
Ensure the planting site has decent drainage to prevent water from pooling around the roots.
Trim the entire clump back hard to halfway above the ground every few years to clear out old thatch.

Don't

Do not plant in constantly waterlogged or boggy soils where oxygen is excluded from the roots.
Do not apply heavy doses of standard fertilizer, as this grass thrives in low-nutrient conditions.
Do not shear the plant into old, leafless woody lower stems.

Seasonal Care Calendar

Task	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Fertilize
Pest Check
Plant
Prune

Watch Out For

Pests & Diseases

Common Pests

Common Diseases

In the Garden

Landscape Uses & Companions

Landscape Uses

Mass PlantingErosion ControlRain GardenBorder EdgingRock GardenContainer Friendly

Companion Plants

Festuca glauca Carex testacea Salvia leucantha Rosmarinus officinalis

Multiply

Propagation Methods

Good to Know

Common Questions

River Mat-rush questions

What zones can River Mat-rush grow in?

River Mat-rush is hardy in USDA Zones 8–10. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.

Is River Mat-rush deer resistant?

Yes — River Mat-rush is rated deer-resistant. Deer typically pass it over, though extreme hunger can override any plant's defenses.

When does River Mat-rush bloom?

River Mat-rush typically blooms in spring through fall. Exact timing shifts a week or two with your zone — Sow's bloom calendar maps it to your garden.

Does River Mat-rush need full sun?

River Mat-rush does best in full sun to part shade. In hot climates, afternoon shade keeps blooms fresher longer.

Is River Mat-rush drought tolerant?

Yes — once established (usually after the first full season), River Mat-rush handles dry spells with minimal watering. Water deeply its first year to build the root system that makes that possible.