Growth Form:Forb/herb, subshrub; plants rounded or low flat-topped mounding; woody base; numerous branches; surfaces covered with soft, weak and thin hairs (pilose).
Leaves: Green; blades narrowly linear, stiff to needle shaped; leaves clustered at nodes in twos or threes; leaves arranged oppositely along stem.
Flower Color: White or off-white with yellow centers, pale yellow; single floral heads with both ray and diskflorets; disk flowers yellow; bracts surrounding heads with ends rounded over (oblong); fruit is a cypsela.
Flowering Season: April or May to October following monsoon rainfall
Elevation: 2,500 to 6,500 feet (762-1,981 m)
Habitat Preferences: Upper deserts, dry and rocky slopes and flats, mesas, caliche or calcareous soils.
Recorded Range: In the United States, Desert Zinnia is limited in distribution; primarily to central and southern Arizona with much smaller isolated populations in NM, TX and UT. It is also native to northern, eastern and central Mexico.
North America & US County Distribution Map for Zinnia acerosa.
North America species range map for Desert Zinnia, Zinnia acerosa:
Click image for full size map
North America species range map for Desert Zinnia, Zinnia acerosa:
Click image for full size map
Genus Information: In North America there are 4native species and 1 accepted taxa overall for Zinnia; there are 3 introduced species. Worldwide, The Plant List includes 22 accepted species names and a further 13 scientific names of infraspecific rank for Zinnia.
In the Southwestern United States: Arizona, Texas and Utah each have 3 species of Zinnia, California and Nevada each have 0 species, New Mexico has 2 species. Data approximate, subject to revision.
Comments: Desert Zinnia has the heart of its United States population in Arizona. Its flowers readily attract insects especially butterflies as noted below. Desert Zinnia differs from the similar Rocky Mountain Zinnia, Zinna multiflora, which has bright yellow flowers. As with other Zinnia’s, Desert Zinnia is a popular arid landscape plant in Arizona and the southwest.
Desert Zinnia, Zinnia acerosa has attractive flowers, the flowers, their seeds and plants may be visited by hummingbirds and/or small mammals including rodents and granivorous birds in search of food, nectar and protection through cover.
Beneficial Value to Butterflies, Honey Bees and Insects
Desert Zinnia, Zinnia acerosa has attractive flowers, the flowers and their plants may be visited or used by butterflies, moths, flies, honeybees, native bees.
****Special Value to Native Bees****
According to The Xerces Society for Invertebrate Conservation, Desert Zinnia, Zinnia acerosa, is recognized by pollination ecologists as attracting large numbers of Native bees. Click here for more information on their Pollinator Conservation Program.
Etymology:
The genus “Zinnia” is from Johann Gottfried Zinn, (1727–1759), a German anatomist and botanist. Mr. Zinn was also a member of the Berlin Academy. It was a botanist, Carl Linnaeus, (1707-1778) who named a genus of flowers in the family Asteraceae, native from Mexico, as “Zinnia” in his honor.
