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Knotted Rush

Juncus nodosus

Last reviewed: August 2026

Knotted Rush (Juncus nodosus)
Photo: Hurd, E.G., S. Goodrich, and N.L. Shaw. / Wikimedia Commons (Public domain)

Toxicity unknown

Knotted Rush (Juncus nodosus) is not listed by the ASPCA Animal Poison Control Center (opens in new tab) or the other sources we check, so we have no verdict for it either way. Absence from those lists is not a clearance. If your pet shows symptoms after eating any plant, call the ASPCA at (888) 426-4435.

The USDA PLANTS Database (opens in new tab) does not flag Knotted Rush as toxic to livestock.

Light

part sun

Water

high

Size

12"–36" H × 4"–12" W

Bloom

Jun, Jul, Aug

Native to

AZ, CA, CO, CT and 28 more states

Before you buy

Your city may pay you to plant this

Cities and water utilities offer rebates for replacing lawn with native and water-wise plants. We track 452 programs across 44 states, each with a link to the provider and the date we last checked it.

Find rebates in your area

Browse plants for this ecoregion

North American DesertsMojave Basin and RangeNorthwestern Forested MountainsSouthern RockiesArizona/New Mexico MountainsChihuahuan DesertsHigh PlainsSouthwestern TablelandsCentral Great PlainsNorthwestern Glaciated PlainsNorthwestern Great PlainsGreat PlainsNorthern Glaciated PlainsWestern Corn Belt PlainsNorthern ForestsNorthern Lakes and ForestsNorth Central Hardwood ForestsDriftless AreaSoutheastern Wisconsin Till PlainsCentral Corn Belt PlainsEastern Corn Belt PlainsSouthern Michigan/Northern Indiana Drift PlainsHuron/Erie Lake PlainsNortheastern HighlandsNortheastern Coastal ZoneNorthern Allegheny PlateauErie Drift PlainMiddle Atlantic Coastal PlainNorthern PiedmontRidge and ValleyInterior River Valleys and HillsAcadian Plains and HillsEastern Great Lakes Lowlands

Knotted rush is a native wetland grass with slender, upright stems and small clusters of brownish flowers. It thrives in consistently moist to wet soils and naturally forms small colonies over time.

In an HOA neighborhood

Knotted Rush takes more care to keep looking intentional in a front yard. Maintenance level: low. Consider it for backyard or mid-zone beds rather than the street edge.

Works well in: backyard only.

  • Looks like an ornamental grass but less refined
  • Requires consistently wet conditions that may appear problematic
  • Brown seed heads can look untidy to conventional tastes

Wildlife value

This rush provides habitat and nesting material for wetland birds and supports various small insects. The seeds are eaten by waterfowl and songbirds.

Common questions

How much sun does Knotted Rush need?
Knotted Rush grows best in part sun conditions.
When does Knotted Rush bloom?
Knotted Rush blooms in June, July, and August.
Where is Knotted Rush native?
Knotted Rush (Juncus nodosus) is native to AZ, CA, CO, CT and 28 more states, per the World Checklist of Vascular Plants (Kew).
Is Knotted Rush toxic to livestock?
The USDA PLANTS Database does not flag Knotted Rush as toxic to livestock.
Is Knotted Rush HOA-friendly?
Knotted Rush takes more care to look intentional in a front yard. Consider it for backyard or mid-zone beds rather than the street edge.

Native range data from the World Checklist of Vascular Plants (Kew). Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.

If something looks wrong

Common plant problems, and what to check first

These come up on almost any plant. Each guide lists the likely causes in the order they are worth ruling out, with one thing to check before you act on any of them, and links to the source it came from.

See all plant problem guides

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