Wildflower/Perennial · Sonoran native
Desert Zinnia
Zinnia acerosa · Asteraceae
Also called: White Desert Zinnia, Wild Zinnia, Spinyleaf Zinnia, Zinnia blanca (Spanish)
Desert Zinnia (Zinnia acerosa) is a very low-water wildflower/perennial native to the Sonoran Desert region well suited to Tucson and the low desert. It grows to 4-10 in H x 8-12 in W (low mounding subshrub) in full sun.
Desert Zinnia at a glance
- Water use
- Very Low (established)
- Sun
- Full sun; thrives in hot, exposed sites with reflected heat.
- Mature size
- 4-10 in H x 8-12 in W (low mounding subshrub)
- Growth rate
- Slow to moderate.
- Bloom
- Small papery white to cream ray flowers (4-6 petals) surrounding a yellow center., Spring through fall (April-October), blooming with warm-season rains, especially after summer monsoon. Long bloom season with available moisture.
- Cold hardiness
- Cold hardy to about 0-10 F (USDA zones 7-10); hardy throughout Tucson.
- Soil
- Well-drained, dry, rocky or sandy/gravelly desert soils; tolerates poor, alkaline, and calcareous soils. Requires excellent drainage.
- Native range
- Native to the Sonoran and Chihuahuan Deserts of the southwestern U.S. (Arizona, New Mexico, Texas) and northern Mexico.
- Best used as
- Groundcover, Small-scale rock/desert garden, Foreground/border edging, Mass planting, Pollinator garden, Low-water xeriscape, Median and parking-lot plantings
- Wildlife
- Nectar source for native bees, butterflies, and other small pollinators. Deer- and rabbit-resistant.
- Toxicity
- Non-toxic; no toxicity reported to people or animals.
How to grow Desert Zinnia in Tucson & the low desert
Watering
Extremely drought tolerant; survives on rainfall once established. Occasional deep irrigation (every 2-3 weeks) in the hottest, driest part of summer extends bloom, but avoid overwatering, which causes rot.
Fertilizer & nutrients
No fertilizer needed; adapted to lean desert soils. Fertilizing is unnecessary and can cause weak, leggy growth.
Pruning & care
Little pruning required; lightly shear in late winter or early spring to remove old growth and maintain a compact, dense mound.
Notes
Tough, compact native mounding perennial/subshrub well suited to low-water Tucson landscapes. Forms a tidy gray-green low mound that whitens with bloom. Excellent for hot, dry, reflected-heat sites where little else thrives; pairs well with other low-desert wildflowers and accents.
Sources: Arizona-Sonora Desert Museum; University of Arizona Cooperative Extension; AMWUA Landscape Plants for the Arizona Desert; Tohono Chul