Rough blazing star | The Morton Arboretum

Rough blazing star is a late summer to early fall perennial with interesting, clustered, pinkish-purple flowers along the tops of tall stems. This species is great in a pollinator garden, native garden, cottage garden, naturalized prairie or meadow, or in more formal beds and borders. The tall, narrow structure of rough blazing star plants can help to create structure and the fuzzy-looking flowers can provide texture among more traditional flowers. This species is native to the Chicago region according to Swink and Wilhelm’s Plants of the Chicago Region and current research.

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

Size and method of spreading:

Rough blazing star plants grow to 3 to 5 feet tall and 2 to 3 feet wide. They spread by self-seeding and producing offsets from their bulblike stem structures (corms).

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

Rough blazing stars are native to the Eastern and Midwestern United States. C-value: 8.

Attracts birds or pollinators:

Rough blazing stars are highly appealing to a number of butterfly species, including black swallowtails, monarchs, and painted ladies. They also attract a variety of bees and birds, especially hummingbirds.

Leaf description:

Rough blazing stars have long, narrow, almost grasslike (linear to narrowly lanceolate) leaves that grow around the bottom portion of the central stem. The leaves are densely crowded and are sometimes mistaken as occurring in whorls, though they are actually in an alternate arrangement. Each leaf has a prominent central vein. The upper and lower surfaces of the leaves can be hairless (glabrous) or have sparse, short hairs (pubescent). The edges of the leaves are often smooth (entire margins), but they can also have a fringe of hair (ciliate margins). The lower leaves attach to the stem via 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 sporadically on the upper end of the central stems of rough blazing stars, and the clusters will mature downwards from the top. The flower heads are stalkless, so they attach directly to the center stem. The flower heads are composed of approximately 14 to 35 individual disk flowers, similar to the centers of daisy flowers, with four or five layers of leaflike structures (bracts) that cup the base of the clusters. These disk flowers have petallike structures (corolla tube) that are 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 bracts surrounding the flower heads have tips that curl inward and edges that are nearly transparent and rough looking, as if they were ripped like paper.

Fruit description:

Rough blazing stars produce small, dry fruit (achenes) comparable to dandelion fruit, which are similarly distributed by the wind. The hairs on the tip of the fruit of rough blazing stars are short, upright, and bristly.