Oenothera caespitosa Nutt.
Viridiplantae > Streptophyta > Streptophytina > Embryophyta > Tracheophyta > Euphyllophyta > Spermatophyta > Magnoliopsida > Mesangiospermae > eudicotyledons > Gunneridae > Pentapetalae > rosids > malvids > Myrtales > Onagraceae > Onagroideae > Onagreae >Oenothera > caespitosa [1]
![Entire plant and rocky substrate from above. Photo by Stan Shebs [2].](/crfs/images/native-plants/plant-directory/tuftedeveningprimrose-first.jpg)
Entire plant and rocky substrate from above. Photo by Stan Shebs [2].
Perennial herbs from taproots and simple or branched, sometimes spreading caudices or rootstocks, acaulescent or rarely with stems to 5 dm long; herbage typically puberulent to villous (especially along leaf margins), glandular, or glabrous; leaves typically in a basal rosette, less commonly along a stem with elongated internodes, mostly 1.5-20 (30) cm long, 0.5-4 cm wide, petiolate, the blades entire, toothed, lobed, or pinnatifid; flowers solitary in leaf axils, sessile or pedicellate, erect or drooping in bud, opening in evening, fragrant; hypanthium 3-14 cm long or more, with nectary glands at the base within; sepals 1.5-5.5 cm long, reflexed at anthesis; petals white, fading white to pink or purplish, 2-6 cm long; anthers 6-15 mm long or more; capsules erect-ascending, 2-5 mm long, woody, tuberculate; seeds numerous, in 2 rows per locule, 2.5-3.5 mm long; 2n = 14 [3].
![Perianth. Photo by Matt Lavin [4].](/crfs/images/native-plants/plant-directory/tuftedeveningprimrose-sec.jpg)
Perianth. Photo by Matt Lavin [4].
Unlike some other Oenothera species, Tufted Evening Primrose has an acaulescent (stemless or nearly so) growth habit [5], with leaves and peduncles arising from the base of the plant. Compared to other acaulescent Oenothera species, the Tufted Evening Primrose has white flowers that fade to pink with age, and the flowers are noticeably fragrant. Other acaulescent Oenothera species have yellow blossoms that fade to purple or pink and are not as fragrant or at all [3].
The common name Tufted Evening Primrose is a misnomer because Oenothera caespitoasa is not, in fact, a primrose (Primula genus of the Primulaceae family) or a rose (Rosa of the Rosaceae family); nor is any other Evening Primrose for that matter. The name “Evening Primrose” is a common name that covers many species and many continents. The plants that go by this common name were given the name by an early botanist who thought the smell of the Oenothera species he was describing was similar to that of the primroses in England [6]. It is important to keep in mind that common names do not always reflect the correct relationships between plants.
![Flower from above. Photo by Miwasatoshi [8].](/crfs/images/native-plants/plant-directory/tuftedeveningprimrose-third.jpg)
Flower from above. Photo by Miwasatoshi [8].
While the human uses of this plant are quite minimal, it does have a wide range of impact with different wildlife. The seeds are eaten by birds [9], and since the tubed blossoms open in the evening, this plant is an important food source for long-tongue hawk moths [5].
Many indigenous tribes used the root [10] and leaves [11] of this plant by grinding it up and placing it on sores or any type of swelling. Specifically, Hopi tribes used the plant to treat sore eyes [5] and Kayenta Navajo used a powdered form of the plant for chafing and a poultice of the whole plant was used for aid in uterine prolapses [12].
![Distribution map Oenothera caespitosa at a county level. Note that the light green in the map indicates that this plant is native to Texas, but was lacking county data [13].](/crfs/images/native-plants/plant-directory/tuftedeveningprimrose-fourth.jpg)
Distribution map Oenothera caespitosa at a county level. Note that the light green in the map indicates that this plant is native to Texas, but was lacking county data [13].
This plant is listed as sensitive in Washington, but considered stable everywhere else [14].
Tufted Evening Primrose is widely distributed and found in most temperate habitats throughout Western North America [5]. Oenothera caespitosa has been split into varieties based on morphological differences, distribution and soil type they grow in. For instance, var. crinita grows where the soils are composed of gravel or clay while var. marinata can also grow in gravelly soils, but will do better than other varieties in soils with large stones. Variety navajoensis is found in clay and sandy soils. It is often considered one of the prettiest desert wildflowers [3] and is favored for planting in rock gardens.
[1] Schoch CL, et al. NCBI Taxonomy: a comprehensive update on curation, resources and tools. Database (Oxford). 2020: baaa062. PubMed: 32761142 PMC: PMC7408187.
[2] Shebs, S. Photo. Oenothera caespitosa var. marginata. near the road in lower Kyle Canyon, Spring Mountains, southern Nevada (elev. about 1600m). https://en.wikipedia.org/wiki/Oenothera_caespitosa#/media/File:Oenothera_caespitosa_var_marginata_3.jpg
[3] Welsh, S. L., Atwood, N. D., Goodrich, S., & Higgins, L. C. (2016). A Utah flora (Third). Monte L. Bean Life Science Museum.
[4] Lavins, M. Photo https://www.flickr.com/photos/plant_diversity/3647214068/in/photostream/
[5] Lesica, Peter, and Walter Fertig. Spring Wildflowers of Utah’s Red Rock Desert. Trillium Press, 2018.
[6] Clare, John. “Plant of the Month, October : Tufted Evening Primrose : Oenothera Cespitosa.” Santa Fe Botanical Garden, Santa Fe Botanical Garden, 1 Oct. 2020, santafebotanicalgarden.org/plant-of-the-month-october-2020/.
[7] Buckley, S., Coburn, F. S., & Hazelton, A. (Eds.). (2010). Oenothera caespitosa. SEINet Portal Network -. Retrieved September 29, 2022, from https://swbiodiversity.org/seinet/taxa/index.php?taxon=Oenothera%2Bcaespitosa&formsubmit=Search%2BTerms
[8] Miwasatoshi. Photo. Oenothera caespitosa, cultivated, Desert Botanical Garden, Phoenix, Arizona. https://commons.wikimedia.org/wiki/File:Oenothera-caespitosa-20080330.JPG
[9] TWC Staff. (2009). Plant database. Lady Bird Johnson Wildflower Center - The University of Texas at Austin. Retrieved September 29, 2022, from https://www.wildflower.org/plants/result.php?id_plant=oeca10
[10] Kindscher, K. (1987). Edible wild plants of the prairie: An ethnobotanical guide. University Press of Kansas.
[11] Jones, Volney H., 1931, The Ethnobotany of the Isleta Indians, University of New Mexico, M.A. Thesis, page 36
[12] Wyman, Leland C. and Stuart K. Harris, 1951, The Ethnobotany of the Kayenta Navaho, Albuquerque. The University of New Mexico Press, page 33
[13] USDA, NRCS. 2022. The PLANTS Database (http://plants.usda.gov, 09/28/2022). National Plant Data Team, Greensboro, NC USA.
[14] USDA. (n.d.). Plants profile for Oenothera caespitosa ssp. caespitosa (tufted evening primrose): USDA plants. PLANTS Profile for Oenothera caespitosa ssp. caespitosa (tufted evening primrose) | USDA PLANTS. Retrieved September 29, 2022, from https://adminplants.sc.egov.usda.gov/java/profile?symbol=OECAC2
