Carnegiea gigantea, Giant Saguaro

Southwest Desert Flora

Home to the plants of the Sonoran, Chihuahuan and Mojave Deserts

Cirsium ochrocentrum, Yellowspine Thistle

Cosmos parviflorus, Southwestern Cosmos

Southwestern Cosmos has showy white, rose, or pinkish flowers. The flower heads have both ray and disk type flowers. Note the tips of the outer petal-like ray flowers have 3 notches. Cosmos parviflorus Southwestern Cosmos, cross-section; note the receptacles are nearly flat and the outer part of the calyx is narrow, elongate and herbaceous. Cosmos parviflorus Southwestern Cosmos fully developed seeds. The cypsela or seed pods are slender with 2 barbs on one end. Cosmos parviflorus Southwestern Cosmos has thin green leaves. The leaves are glabrous, pinnatifid or dissected into arrow thread-like lobes segments. Cosmos parviflorus Southwestern Cosmos blooms from July to October and prefers elevations from 4,000 to 9,000 feet (1,219-2,743 m). Preferred habitats vary from open areas in pine communities, on slopes, hillsides and canyons and disturbed areas. Cosmos parviflorus

Scientific Name: Cosmos parviflorus
Common Name: Southwestern Cosmos

Also Called: Wild Cosmos

Family: Asteraceae, Sunflower Family

Synonyms: (Coreopsis parviflora)

Status: Native

Duration: Annual

Size: 2½ feet (76 cm) or more

Growth Form: Forb/herb; erect, tall slender stems and leaves, mostly glabrous.

Leaves: Green; thin, arranged opposite along the stem, the leaves are dissected into narrow lobes (pinnatifid); smooth (glabrous).

Flower Color: White, rose or pinkish; attractive, flower heads with both ray and disk florets, outer ray petals usually with 3 notched; the fruit is a cypsela.

Flowering Season: June or July through October

Elevation: 4,000 to 9,000 feet (1,219-2,743 m)

Habitat Preferences: Open areas in pine communities, also on slopes, hillsides and canyons and disturbed areas.

Recorded Range: In the United States, Southwestern Cosmos is a southwestern native in AZ, CO, NM and TX. It is also reported, apparently as an introduced species in MA, MD, ME, MO, RI.

It also in native to Baja California and northern and central Mexico.

In the Southwestern part of the United States it is found mostly in New Mexico and Arizona.

North America & US County Distribution Map for Cosmos parviflorus.

North America species range map for Cosmos parviflorus:
North American range map courtesy of Virginia Tech, Dept. of Forest Resources & Environmental Conservation

North America species range map for Cosmos parviflorus: Click on image for full size map.
Click image for full size map

U.S. Weed Information: Unknown
Invasive/Noxious Weed Information: Unknown

Wetland Indicator: In North America Cosmos parviflorus has the following wetland designations:

  • Arid West, FACU;
  • Atlantic and Gulf Coastal Plain, FAC;
  • Great Plains, FAC;
  • Midwest, FACU;
  • Northcentral & Northeast, FACU;
  • Western Mountains, Valleys, and Coast, FACU;

  • FACU = Facultative Upland, usually occur in non-wetlands, but may occur in wetlands
    FAC = Facultative Hydrophyte, Occur in wetlands and non-wetlands

    Threatened/Endangered Information: Unknown

    Genus Information: In North America there are 4 species and 4 accepted taxa overall for Cosmos. In North America 2 of the 4 species are native and 2 species are listed as invasive. Worldwide, The Plant List includes 42 accepted species names and a further 59 scientific names of infraspecific rank for the synonym genus Cosmos.

    The genus Cosmos was published by Antonio José Cavanilles in 1791.

    In the Southwestern United States: Arizona, California, New Mexico and Texas each have 2 species of Cosmos, Nevada has 0 species and Utah has 1 species. The 2 species include the native Cosmos parviflorus, and 1 invasive species Garden Cosmos, Cosmos bipinnatus. All data approximate and subject to revision.

    Comments: Southwestern Cosmos is a native species in the southwest United States that has the center of its population in New Mexico. It is found in higher elevations in Arizona where it does well with ample summer rainfall although it is never profuse or observed in large numbers.

    A similar landscape cultivated species, the Garden Cosmos, Cosmos bipinnatus, is native to Mexico and is more robust with larger flowers in pink, purple or white.

    Importance to Wildlife, Birds and Livestock
    Cosmos parviflorus flowers are visited regularly by hummingbirds, nectar-feeding bats and small mammals in search of nectar. Southwestern Cosmos is grazed by livestock.

    Special Value to Native Bees, Butterflies and Insects
    Cosmos parviflorus is recognized as having special value to Native bees. Their flowers and forage my also be visited by butterflies and other small insects.

    Click here to read about The Xerces Society's Pollinator Conservation Program or visit The Xerces Society for Invertebrate Conservation at

    The genus Cosmos (Cos'mos:) from the Greek kosmos, “ornament, decoration”.

    The genus Cosmos was published by Antonio José Cavanilles in 1791.

    The species epithet parviflorus (parviflor'a/parviflor'um/parviflor'us:) is from the Greek words parvus, meaning, “small,” and flora, meaning, “flower,” thus “small-flowered”.

    Cosmos parviflorus was used by southwestern United States indigenous peoples.
  • Navajo, Ramah Drug, Ceremonial Medicine, Cold infusion of dried leaves used as ceremonial chant lotion plant parts, use.

  • See complete listing of ethno-botanical uses at Native American Ethnobotany, University of Michigan, Dearborn.

    Date Profile Completed: 06/27/2012; updated 06/28/2020
    Arizona Flora, Kearney, Thomas H., Peebles, Robert H., 1960, University of California Press, Berkley and Los Angeles
    U.S. Dept. of Agriculture, Natural Resources Conservation Service on-line database and USGS ITIS search - (accessed 06/27/2020) for Comos
    The Plant List (2013). Version 1.1. Published on the Internet; (accessed 06/27/2020).
    Robert W. Kiger, FNA | Family List | FNA Vol. 21 | Asteraceae | Cosmos; 3. Cosmos parviflorus (Jacquin) Persoon, Syn. Pl. 2: 477. 1807. Flora of North America Editorial Committee, eds. 1993+. Flora of North America North of Mexico. 16+ vols. New York and Oxford.
    FNA 2006, Kearney and Peebles 1969, McDougall 1973; Editor: L.Crumbacher 2011;
    FNA 2006, Kearney and Peebles 1969, McDougall 1973; Editor; L. Crumbacher 2011 from SEINet Field Guide, on-line; (accessed 06/27/2020).
    Native Plant Information Network, NPIN (2013). Published on the Internet - (accessed 06/27/2020). Lady Bird Johnson Wildflower Center at The University of Texas, Austin, TX.
    Wikipedia contributors, 'Cosmos parviflorus', Wikipedia, The Free Encyclopedia, 22 March 2018, 05:45 UTC, [accessed 27 June 2020]
    Kleiman, Russ, Dr., Associate Botanist, Dale A. Zimmerman Herbarium; Vascular Plants of the Gila Wilderness; Cosmos parviflorus; (accessed 06/27/2020) Presented in Association with the Western New Mexico University Department of Natural Sciences
    Aggie-Horticulture, Ornamental Plants Klein Cholla, Tasajillo, Candle Cholla; (accessed: 06/27/2020)
    SEINet for synonyms, scientific names and recorded geographic locations,
    Michael J. Plagens, Sonoran Desert Naturalist; Southern Fire Ant, Solenopsis xyloni; on-line; accessed 06/27/2020