Carnegiea gigantea, Giant Saguaro

Southwest Desert Flora

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

Cirsium ochrocentrum, Yellowspine Thistle

Crossosoma bigelovii, Ragged Rockflower

Crossosoma bigelovii, Ragged Rockflower, Southwest Desert Flora Crossosoma bigelovii, Ragged Rockflower, Southwest Desert Flora Crossosoma bigelovii, Ragged Rockflower, Southwest Desert Flora Crossosoma bigelovii, Ragged Rockflower, Southwest Desert Flora

Scientific Name: Crossosoma bigelovii
Common Name: Ragged Rockflower
Also Called: Bigelow's Crossosoma, Ragged Rock Flower, Ragged Rock-flower, Rhyolite Bush
Family: Crossosomataceae, Crossosoma Family
Synonyms: ()
Status: Native
Duration: Perennial
Size: Up to 8 feet tall but typically much smaller.
Growth Form: Shrub or subshrub; woody, rough bark, erect with multiple branches, branches armed with thorny spines.
Leaves: Green or gray-green; in clusters, deciduous under drought conditions.
Flower Color: White with pink or purple tinges; showy flowers, accurately described as resembling an apple-blossom with its numerous stamens, fruit is a small 2mm follicle containing several seeds.
Flowering Season: February to May, longer under favorable conditions.
Elevation: 1,500 to 4,000 feet.

Habitat Preferences: Dry rocky slopes, cliffs and canyon walls.

Recorded Range: Crossosoma bigelovii is relatively rare in the United States where it occurs in Arizona, California and Nevada. This species is also native to Baja California, Chihuahua, and Sonora Mexico. In Arizona it is found mostly in the western half of the state.

North America & US County Distribution Map for Crossosoma bigelovii.

U.S. Weed Information: No information available.
Invasive/Noxious Weed Information: No information available.
Wetland Indicator: No information available.
Threatened/Endangered Information: No information available.

Genus Information:
2 species in Crossosoma in the United States (California), 1 found in Arizona. Crossosoma bigelovii has 2 varieties;
Crossosoma bigelovii var. bigelovii, Ragged Rockflower, original distribution above and
Crossosoma bigelovii var. glaucum, Ragged Rockflower, which is found only in Arizona.

Comments: Ragged Rockflower is one of only 7 species from the Crossosomataceae family found in North America north of Mexico.

Although not common, Ragged Rockflower is used as a landscape specimen if a natural look is desired as the flowers have a beautiful aroma, attract butterflies and plants can be grown from seed. Ragged Rockflower lives in crags and crevices on cliff ridges where water is quickly drained away so caution is required as over-watering these plants can be detrimental.

Date Profile Completed: 4/30/2015, rev. 07/22/2015
U.S. Dept. of Agriculture, Natural Resources Conservation Service on-line database and USGS ITIS search
Arizona Flora, Kearney, Thomas H., Peebles, Robert H., 1960, University of California Press, Berkley and Los Angeles, California.
Mason, Charles T., Jr. Crossosomataceae, Journal of Ariz. and Nev. Academy of Science. (JANAS) 26(1):2.
Native Plant Information Network, NPIN (2013). Published on the Internet [accessed:4/30/2015]. Lady Bird Johnson Wildflower Center at The University of Texas, Austin, TX.
1993, The Jepson Manual, Citation: (accessed4/30/2015)
Wikipedia contributors, 'Crossosoma bigelovii', Wikipedia, The Free Encyclopedia, 24 September 2014, 18:47 UTC, [accessed 30 April 2015]
SEINet for synonyms, scientific names and recorded geographic locations,