Family: Nyctaginaceae - Four O'Clock Family
Perennial herbs from a taproot; stems are 7.1” to 3.3' (1.8 to 10 dm) long
Leaves: opposite; simple; sticky hairs on the leaves; egg-shaped or linear; entire; 0.32” to 3.6” (8 to 90 mm) long, 0.12” to 1.2” (3 to 37 mm) wide
Flowers: 0 petals; 4 to 5 united colored petaloid sepals; sepaloid bracts (bracts mimic the sepals); 1 to many stamens; 1 pistil; flowers borne in dense clusters of 25 to 80 flowers; tube-shaped corolla; tube is 0.4” to 1” (10 to 25 mm) long; flowers are usually white, sometimes tinged with green, lavender or pink
Pollinators: other genera in this family are pollinated by insects such as moths, etc.
Fruits: achene; not splitting open at maturity
Blooms in Arches National Park: April, May, June, July, August, September, October
Habitat in Arches National Park: often in sand in desert shrub and pinyon-juniper communities
Location seen: park entrance road, park road mile 1 to 3, park road between Moab fault and Park Avenue, Park Avenue, Windows
Other: The genus name, “Abronia”, is from the Greek "abros" meaning “delicate” referring to the flowers. The species name, “fragrans”, means “fragrant” and refers to the sweet-smelling flowers that open in late afternoon and close in the morning. Sand grains adhere to the sticky hairs on the leaves.
Flowers bloom late in the day giving the family its common name – four o'clock. The family is mostly native to the tropics.
Last updated: November 14, 2021