Wildflower/Perennial · Sonoran native
Tufted Evening Primrose
Oenothera caespitosa · Onagraceae
Also called: White Evening Primrose, Fragrant Evening Primrose, Gumbo Lily, Tufted Sundrops, Desert Evening Primrose
Tufted Evening Primrose (Oenothera caespitosa) is a low-water wildflower/perennial native to the Sonoran Desert region well suited to Tucson and the low desert.
Tufted Evening Primrose at a glance
- Water use
- Low (established)
- Sun
- Full sun to light afternoon shade; needs sun for best bloom but appreciates some afternoon protection in the hottest sites.
- Mature size
- 6-12 in H x 12-24 in W (low, stemless rosette spreading clump)
- Growth rate
- Slow to moderate.
- Bloom
- Large showy white flowers (3-4 in across) that open in the evening and fade to pink/rose by the next afternoon; fragrant., Spring (March-May), sometimes again after summer rains; flowers open at dusk and close the following day.
- Cold hardiness
- Cold hardy to about -20 to -30 F (USDA zones 4-9); fully hardy in Tucson.
- Soil
- Well-drained sandy, gravelly, or rocky soils; tolerates poor and alkaline desert soils. Excellent drainage is essential; rots in heavy wet soil.
- Native range
- Native to the western and southwestern U.S. including Arizona; occurs in the Sonoran Desert and adjacent higher-elevation areas.
- Best used as
- Foreground/border, Rock and desert gardens, Groundcover-scale accent, Pollinator/moth garden, Naturalized wildflower plantings, Low-water xeriscape
- Wildlife
- Large fragrant night-opening flowers are pollinated by hawkmoths (sphinx moths); also visited by native bees. Deer-resistant.
- Toxicity
- Non-toxic; no significant toxicity reported.
How to grow Tufted Evening Primrose in Tucson & the low desert
Watering
Drought tolerant once established; water deeply and infrequently. Occasional irrigation (every 2-3 weeks) in spring and dry summer heat prolongs bloom, but avoid overwatering and standing water.
Fertilizer & nutrients
Minimal to no fertilizer; adapted to lean soils. A very light spring feeding is optional but generally unnecessary.
Pruning & care
Little pruning needed; remove spent flower stalks and tidy dead foliage. Cut back tattered growth in late winter to refresh the rosette.
Notes
Stemless, low rosette-forming native perennial prized for its large, fragrant, evening-opening white flowers that age to pink. Best in well-drained, gritty soils with restrained water; short-lived in overly irrigated beds. Distinct from the aggressive pink-flowered Mexican evening primrose (Oenothera berlandieri/speciosa) — this species is clumping and well-behaved.
Sources: Arizona-Sonora Desert Museum; University of Arizona Cooperative Extension; AMWUA Landscape Plants for the Arizona Desert; Tohono Chul; USDA PLANTS Database