Wildflower/Perennial · Sonoran native
Paperflower
Psilostrophe cooperi · Asteraceae
Also called: Cooper's Paperflower, Whitestem Paperflower, Yellowpaper Daisy
Paperflower (Psilostrophe cooperi) is a very low-water wildflower/perennial native to the Sonoran Desert region well suited to Tucson and the low desert. It grows to 12-18 in H x 12-20 in W (to about 2 ft) in full sun, with a moderate growth rate. Expect bright golden yellow blooms spring.
Paperflower at a glance
- Water use
- Very Low (established)
- Sun
- Full sun; tolerates reflected heat
- Mature size
- 12-18 in H x 12-20 in W (to about 2 ft)
- Growth rate
- Moderate
- Bloom
- Bright golden yellow, Spring (peak March-May) and again after summer monsoon rains into fall; can bloom intermittently much of the year
- Cold hardiness
- Hardy to about 0-10 F; USDA zones 7-10
- Soil
- Sandy, gravelly or rocky well-drained soils; tolerant of poor, alkaline desert soils; requires good drainage
- Native range
- Sonoran, Mojave and Chihuahuan Deserts of Arizona, California, Nevada, Utah, New Mexico and northern Mexico
- Best used as
- Wildflower and xeriscape gardens, Mass plantings and color accent, Rock gardens, Naturalized desert landscapes, Dried-flower interest
- Wildlife
- Nectar source for native bees, butterflies and other pollinators.
- Toxicity
- Contains compounds toxic to livestock (notably sheep) in quantity; generally not a significant hazard in ornamental home-landscape settings.
How to grow Paperflower in Tucson & the low desert
Watering
Very drought tolerant once established; little to no supplemental irrigation needed beyond occasional deep soaks every 3-4 weeks in the hottest, driest stretches. Excess water shortens its life.
Fertilizer & nutrients
Not needed; performs best in lean, unimproved desert soil. Avoid fertilizing.
Pruning & care
Shear back lightly after the main bloom flush to remove spent papery flowers and encourage reblooming and a tidy mounded form. Cut back hard in late winter to refresh; tends to be short-lived (3-5 years) but reseeds.
Notes
Named for the papery flower heads that dry and persist on the plant, fading to straw color and providing lasting interest. A compact, cheerful golden mound well suited to low-water Tucson gardens; reseeds readily.
Sources: University of Arizona Cooperative Extension; Arizona-Sonora Desert Museum; AMWUA Landscape Plants for the Arizona Desert; Tohono Chul