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pink evening primrose, rose evening-primrose

Mexican evening primrose, pinkladies, showy evening primrose

Habit Herbs perennial, caulescent, strigillose and often also sparsely hirsute; from slender taproot. Herbs perennial, caulescent, glabrate to strigillose, usually also sparsely hirsute; from slender taproot and spreading by rhizomes.
Stems

1–several, ascending to decumbent, 7–65 cm.

many, erect, 4–60 cm.

Leaves

in a basal rosette and cauline, basal 1–6 × 0.3–2 cm, blade narrowly elliptic to elliptic or ovate, margins subentire, weakly serrulate, or sinuate-pinnatifid;

cauline 1–6 × 0.3–2 cm, blade narrowly elliptic to narrowly ovate, margins subentire or weakly serrulate, proximal ones sinuate-pinnatifid.

in a basal rosette and cauline, basal 2–9 × 0.3–3.2 cm, blade oblanceolate to obovate, margins subentire or sinuate-pinnatifid;

cauline 1–10 × 0.3–3.5 cm, blade narrowly elliptic to ovate, margins subentire or serrulate to sinuate-pinnatifid.

Inflorescences

erect.

sharply nodding.

Flowers

1–3 opening per day near sunrise;

buds with free tips 0.1–1 mm;

floral tube 4–8 mm;

sepals 6–12 mm;

petals rose purple, fading darker, 4–12 mm;

filaments 4–6 mm, anthers 2–3.5 mm, pollen 35–65% fertile;

style 7–13.5 mm, stigma surrounded by anthers at anthesis.

1–3 opening per day near sunrise in some populations, near sunset in others;

buds with free tips 0–4 mm;

floral tube 12–25 mm;

sepals 15–50 mm;

petals pink to rose, fading darker, or white, fading pink, 15–45 mm;

filaments 10–22 mm, anthers 6–16 mm, pollen 85–100% fertile;

style 20–55 mm, stigma exserted beyond anthers at anthesis.

Capsules

narrowly obovoid, 4–12 × 2–4 mm, apex attenuate to a sterile beak, proximal stipe 5–20 mm, gradually tapering to base, valve midrib prominent in distal part;

sessile.

narrowly obovoid to narrowly rhombic-ellipsoid, angled, 10–25 × 3.5–6 mm, apex attenuate to a sterile beak, valve midrib prominent, proximal stipe cylindrical, not tapering to base, (4–)8–15 mm;

sessile.

Seeds

narrowly obovoid, 0.5–0.9 × 0.3–0.5 mm.

narrowly obovoid, 1–1.2 × 0.5–0.6 mm.

2n

= 14.

= 14, 28, 42.

Oenothera rosea

Oenothera speciosa

Phenology Flowering Mar–Sep. Flowering (Feb–)Apr–Jul(–Oct).
Habitat tropical areas.. Grasslands, glades, open woodlands, disturbed places, pastures, rail­roads, roadsides, loamy or sandy soil, sometimes clay.
Elevation 10–600 m. (0–2000 ft.) 10–900 m. (0–3000 ft.)
Distribution
from FNA
AZ; CA; TX; Mexico; Central America; West Indies; tropical areas [Introduced in South America (Argentina), Europe, Asia, s Africa, Atlantic Islands (Azores, Canary Islands)]
[WildflowerSearch map]
[BONAP county map]
from FNA
AR; IA; IL; IN; KS; LA; MO; NE; NM; OK; TX; Mexico (Chihuahua, Coahuila, Durango, Nuevo León, San Luis Potosí, Tamaulipas)
[WildflowerSearch map]
[BONAP county map]
Discussion

Oenothera rosea is a PTH species, forming a ring of 14 chromosomes in meiosis, and is self-compatible and autogamous. In the flora area, it is known from Cochise, Pima, and Santa Cruz counties in Arizona, Alameda, Los Angeles, Riverside, San Bernardino, San Diego, San Francisco, and Santa Barbara counties in California (primarily in urban areas), and from southern Texas. It is clearly of North American origin, since all of its close relatives are confined to North America, and has spread south along the Andes. It occurs at 500–3700 m in South America but generally at lower elevations in most areas.

The name Hartmannia affinis Spach is illegitimate, being based on Oenothera virgata; H. gauroides Spach is also illegitimate, being based on O. rosea; O. purpurea Lamarck is a later homonym; these three names pertain here.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Oenothera speciosa is widely cultivated worldwide for its showy flowers and easy maintenance. It is not known to be definitely naturalized, but tends to persist or become adventive due to its aggressive vegetative reproduction.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 10. FNA vol. 10.
Parent taxa Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Hartmannia Onagraceae > subfam. Onagroideae > tribe Onagreae > Oenothera > sect. Hartmannia
Sibling taxa
O. acutissima, O. albicaulis, O. argillicola, O. arida, O. arizonica, O. biennis, O. boquillensis, O. brachycarpa, O. calcicola, O. californica, O. canescens, O. capillifolia, O. cavernae, O. cespitosa, O. cinerea, O. clelandii, O. coloradensis, O. cordata, O. coronopifolia, O. coryi, O. curtiflora, O. curtissii, O. deltoides, O. demareei, O. dodgeniana, O. drummondii, O. elata, O. engelmannii, O. falfurriae, O. filiformis, O. filipes, O. flava, O. fruticosa, O. gaura, O. gayleana, O. glaucifolia, O. glazioviana, O. grandiflora, O. grandis, O. harringtonii, O. hartwegii, O. havardii, O. heterophylla, O. hispida, O. howardii, O. humifusa, O. jamesii, O. kunthiana, O. laciniata, O. lavandulifolia, O. lindheimeri, O. linifolia, O. longissima, O. macrocarpa, O. mckelveyae, O. mexicana, O. nealleyi, O. neomexicana, O. nutans, O. nuttallii, O. oakesiana, O. organensis, O. pallida, O. parviflora, O. patriciae, O. perennis, O. pilosella, O. platanorum, O. podocarpa, O. primiveris, O. psammophila, O. pubescens, O. rhombipetala, O. riparia, O. serrulata, O. sessilis, O. simulans, O. sinuosa, O. spachiana, O. speciosa, O. stricta, O. suffrutescens, O. suffulta, O. tetraptera, O. texensis, O. toumeyi, O. triangulata, O. triloba, O. tubicula, O. villosa, O. wolfii, O. xylocarpa
O. acutissima, O. albicaulis, O. argillicola, O. arida, O. arizonica, O. biennis, O. boquillensis, O. brachycarpa, O. calcicola, O. californica, O. canescens, O. capillifolia, O. cavernae, O. cespitosa, O. cinerea, O. clelandii, O. coloradensis, O. cordata, O. coronopifolia, O. coryi, O. curtiflora, O. curtissii, O. deltoides, O. demareei, O. dodgeniana, O. drummondii, O. elata, O. engelmannii, O. falfurriae, O. filiformis, O. filipes, O. flava, O. fruticosa, O. gaura, O. gayleana, O. glaucifolia, O. glazioviana, O. grandiflora, O. grandis, O. harringtonii, O. hartwegii, O. havardii, O. heterophylla, O. hispida, O. howardii, O. humifusa, O. jamesii, O. kunthiana, O. laciniata, O. lavandulifolia, O. lindheimeri, O. linifolia, O. longissima, O. macrocarpa, O. mckelveyae, O. mexicana, O. nealleyi, O. neomexicana, O. nutans, O. nuttallii, O. oakesiana, O. organensis, O. pallida, O. parviflora, O. patriciae, O. perennis, O. pilosella, O. platanorum, O. podocarpa, O. primiveris, O. psammophila, O. pubescens, O. rhombipetala, O. riparia, O. rosea, O. serrulata, O. sessilis, O. simulans, O. sinuosa, O. spachiana, O. stricta, O. suffrutescens, O. suffulta, O. tetraptera, O. texensis, O. toumeyi, O. triangulata, O. triloba, O. tubicula, O. villosa, O. wolfii, O. xylocarpa
Synonyms Gaura epilobia, Godetia heuckii, Hartmannia rosea, H. rosea var. parvifolia, H. virgata, O. psycrophila, O. rosea var. parvifolia, O. rubra, O. virgata, Xylopleurum roseum Hartmannia berlandieri, H. reverchonii, O. berlandieri, O. delessertiana, O. hirsuta, O. obtusifolia, O. shimekii, O. spachii, O. speciosa var. berlandieri, O. speciosa var. childsii, O. tetraptera var. childsii, Xylopleurum berlandieri, X. drummondii, X. hirsutum, X. obtusifolium, X. speciosum
Name authority L’Héritier ex Aiton: Hort. Kew. 2: 3. (1789) Nuttall: J. Acad. Nat. Sci. Philadelphia 2: 119. (1821)
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