Nassella tenuissima

Latin Name: Nassella tenuissima
Common Name: Silky Thread Grass
Mature Height (ft): 18-24"
Mature Width: 8-12"

Mature Shape

Upright clumping warm season grass.
Mulch: Inorganic.

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A mid height grass suitable for any low water-use garden, city or country. It does self-seed somewhat, but I hadn’t noticed it to be a problem in a xeric setting (simply remove or transplant them). It's greatest attribute is it's gently flowing nature int he wind. It is native to Texas and the southwest. I saw it growing along the slopes of the Chisos Mountains in Big Bend National Park. It pairs well with yucca, agave, Calylophus and any native shrub.

Nasella tenuissima (formerly Stipa tenuissima) is a case in point to read several references when trying to determine a plant’s suitability for our climate. Flora, A Gardener’s Encyclopedia, describes it cold hardy for Zones 9 – 11. It survives quite nicely to Zone 5. Although a well thought of reference, I have found its information regarding our southwest, drought tolerant type plants incomplete.

The golden groundcover in the foreground is Origanum vulgare ‘Aureum’, golden oregano. The low water-use rose is Rosa, ‘Zephirine Drouhin’.


Use in Garden

Sunny location, sun/part shade. Xeriscape bed. Native plant bed. Ornamental grass garden. Habitat garden.


Cut back this gracefully flowing grass at winter’s end, and rake out any dead grass during the summer, if necessary. The neighborhood cats have turned my silky thread grass bed into their cat bed, so cutting and fluffing during the summer is necessary to revive its appearance for me.