Content Detail

Rocky Mountain blazing star is a midsummer to early fall perennial that has showy, bright pinkish-purple flowers that are irresistible to butterflies, including monarchs. This is a great selection to create structure and texture for a native, pollinator, or wildflower garden.

  • Family (English) Aster
  • Family (botanic) Asteraceae
  • Tree or plant type Perennial
  • Native locale Illinois, North America
  • Size range Medium plant (12-24 inches), Large plant (more than 24 inches)
  • Light exposure Full sun (6 hrs direct light daily)
  • Hardiness zones Zone 3, Zone 4, Zone 5 (Northern Illinois), Zone 6 (City of Chicago), Zone 7, Zone 8
  • Soil preference Alkaline soil, Dry soil, Sandy soil, well-drained soil
  • Tolerances Dry sites, Occasional drought
  • Season of interest midsummer, late summer, early fall
  • Flower color and fragrance Pink, Purple
  • Shape or form Narrow, Upright
  • Growth rate Moderate
  • Wildlife Birds, Butterflies, Hummingbirds, Insect pollinators

Size and method of spreading:

At maturity, Rocky Mountain blazing stars are 1 to 3 feet tall and one-half  to 2 feet wide. They spread by self-seeding. Underground bulblike structures (corms) will sometimes produce offsets as a means of spreading.

Native geographic location and habitat: (include C-value if appropriate)

Rocky Mountain blazing stars are native to the Central United States.

Attracts birds or pollinators: 

Rocky Mountain blazing stars are highly attractive to butterflies and birds, including monarch butterflies and hummingbirds. Numerous species of bees are also drawn to the flower heads.

Leaf description:

Rocky Mountain blazing stars have leaves that grow around the bottom portion of the central stem. The leaves are in an alternate arrangement along the central stem. Each leaf has a prominent central vein. The lower leaves are long, narrow, and sometimes widened near the tip (oblong-spatulate). The leaves higher on the central stem are thinner and widen towards the center (oblong-elliptic). The upper and lower surfaces of the leaves have sparse, short hairs (pubescent). The edges of the leaves are smooth (entire margins). The lower leaves attach to the stem via long stalks (petioles), whereas the higher leaves may attach directly to the stem (sessile).

Flower description:

Clusters of purplish-pink flowers that are about 1 inch in diameter develop on the upper end of the central stems of Rocky Mountain blazing stars, and the clusters will mature downwards from the top. The flowerheads have individual stalks that attach to the center stem. The flower heads are composed of approximately 30 to 100 individual disk flowers, similar to the centers of daisy flowers, with four or five layers of leaflike structures (bracts) that surround the base of the flower heads. These disk flowers have petallike structures (corolla tube) that form a star shape (five-lobed). Curly, stringlike structures (long-divided style) protrude from the center of each flower, giving the clusters an almost fuzzy appearance. There is a dark reddish-brown tube (connate staminate tubes) around each long-divided style. The four or five layers of bracts surrounding the flower heads have edges that are reddish magenta and rough looking, as if they were ripped like paper.

Fruit description:

Rocky Mountain blazing stars produce small, dry fruit (achene) comparable to dandelion fruit, which are similarly distributed by the wind. The hairs on the tip of the fruit of Rocky Mountain blazing stars are short, bristly, and barbed.

Plant Care:

This is a low-maintenance, tough plant that does not require a lot of care. Staking can help to support taller stems. Take care to not overwater Rocky Mountain blazing stars.

List of pests, diseases, and tolerances:

No serious pest or disease issues affect Rocky Mountain blazing stars, but thrips can be minor pests.


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