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wrinkled jointtail grass

Coelorachis rugosa · Poaceae

wrinkled jointtail grass (Coelorachis rugosa)
Photo: Internet Archive Book Images · Public domain · via Wikimedia Commons

wrinkled jointtail grass (Coelorachis rugosa) is a perennial grass or grass-like plant in the Poaceae family. It is native to North America. USDA records it as hardy in zone 6 and warmer, down to about -8°F.

At a glance

Typegraminoid USDA
Lifecycleperennial USDA
Native statusnative USDA
Mature height2 ft USDA
Lightpart-shade USDA
Water needmedium USDA
Growth ratemoderate USDA
Soil pH5–7 USDA
BloomAugust–September USDA
Flower colorWhite USDA
Hardiness zones6 and warmer USDA
Guild layerherb-layer Derived
Nursery availabilityNo Known Source USDA

USDA quoted from the USDA PLANTS database · Derived computed by a fixed rule from those columns. No value on this page is estimated.

Growing conditions

It grows in partial shade. USDA rates it as having moderate water needs. Its drought tolerance is rated low. It is recorded on soils from pH 5 to 7 — a broad range that spans acidic through mildly alkaline ground. Its cold limit is zone 6.

Size and growth

At maturity it reaches about 2 ft, making it about knee height. It grows at a moderate rate.

Bloom period

USDA records a bloom period of August through September. Flowers are white.

A flowering date, not a pollinator rating.

Foliage, flower and season

Summer foliage is green, fine in texture. Its flowers are not conspicuous — a plant for form and foliage. Its active growth period is spring and summer. USDA rates its lifespan as moderate.

What the site needs to provide

USDA records it across sites receiving 45 to 80 inches of annual precipitation. It needs at least 150 frost-free days to finish its season. It roots to at least 6 inches. Fertility requirement: low — no feeding needed on ordinary garden soil.

Propagating it

Seed is the only propagation method USDA lists. Division and cuttings are not listed as options. USDA records no cold-stratification requirement, so seed should germinate without a chilling period. Its seed spreads at a slow rate. It does not spread vegetatively, so it will stay where you put it.

Resilience and wildlife

Browsing animals rate it barely palatable — the sourced basis for calling it deer-resistant. Its fire tolerance is rated none. Its growth form is recorded as bunch.

Role in a guild

Herb layer. In a layered planting this is the herbaceous middle — perennials and grasses that fill the space between ground cover and shrubs. The layer is derived by a fixed rule from growth habit and mature height.

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Tags

deciduousclay-tolerantdeer-resistantnative

Related plants

Others in Coelorachis

Similar role and hardiness

Where this data comes from

Every value on this page comes from the USDA PLANTS database record for symbol CORU3, or is computed from those values by a fixed rule. Nothing here is estimated or model-generated. Where USDA publishes no value, this page omits the claim rather than filling the gap.

Read our full data sources and methodology.

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