Sundrops and Evening Primrose

Oenothera
Perennials and biennials, that are mostly hardy zones 5 to 9 in full sun to partial shade on light sandy soil though soil tolerant.
Propagation is from seed, soft cuttings or division while dormant.
The young leaves of the Primrose can be eaten as a pot herb if boiled for 20 minutes in a change of water.
The abundant immature seed pods are edible and can be added to salads.

Oenothera acaulis
A dwarf, turfed perennial, reaching a maximum size of 8 inches x 2 feet, that is native to Chile.
The coarsely-toothed, Dandelion-shaped leaves are up to 8 inches in length.
The white ( fading to pink ), saucer-shaped flowers, up to 3.2 inches across, are borne all summer long. The flowers open during the evening.
Hardy zones 4 to 9 in full sun to partial shade.
Great for rock gardens.

'Aurea'
Yellow flowers

Oenothera 'African Sun'
Forms a low, perennial carpet, reaching up to 6 inches in height, with rich green foliage and very abundant golden-yellow flowers all summer long. The flowers are up to 1 inch across. It can be used as a border and looks great cascading over walls.
Hardy zones 4 to 9 in full sun to partial shade. It is very drought tolerant.

Oenothera berlandieri ( Mexican Evening Primrose )
A fast growing, mat-forming perennial. It is considered by some to be a subspecies of Oenothera speciosa. It is found on rocky savanna and prairie in the wild.
The oblanceolate leaves are up to 3 x 0.5 inches in size. The fuzzy foliage is gray-green.
The white to pale pink flowers, up to 3 inches wide, are only open during the daytime. They appear during late spring into early autumn.
Hardy zones 4 to 9 in full sun to partial shade on well drained soil. Very tolerant of drought and heat.

'Siskiyou'
Very fast growing, reaching a maximum size of 1.4 x 6 ( often only half this in height ) feet.
The fragrant, pink flowers, up to 3 inches across, are borne abundantly all summer long.
May be invasive on sites that are fertile.

* photos of unknown internet source




* photo taken on June 1 2010 in Columbia, MD

* photos taken on May 26 2012 in Columbia, MD

* photo taken on June 22 2013 in Columbia, MD

'Woodside White'
Fast growing, reaching a maximum size of 1.5 x 6 ( rarely over 1 in height ) feet.
The fragrant, pure white ( with bright green throat ) flowers, up to 3 inches across, are borne all summer long. The flowers fade to pink as they age.
May be invasive on sites that are fertile.

Oenothera biennis ( Common Evening Primrose )
A biennial, reaching up to 6.5 ( rarely over 4.5 ) feet in height, that is native to eastern North America ( from Kitsault, British Columbia to Edmonton, Alberta to Winnipeg, Manitoba to Kenora, Ontario to Lake Nipigon, Ontario to Chapleau, Ontario to Chalk River, Ontario to southern Quebec to Newfoundland; south to Montana to central Oklahoma to central Florida ). In the Windsor/Essex County, Ontario region; it was found throughout the region and was especially abundant at Point Pelee and the Ohio shore during the 1800s. It is found on roadsides, wood edges and sandy prairies in the wild.
The hairy, lance-shaped to oblong leaves are up to 7 x 2.5 inches in size. The foliage is mid-green.
The fragrant, pale yellow flowers, up to 2.3 inches wide, open during the evening or cloudy days. They are borne early summer to mid-autumn.
Oil from the seed contains gamma-linolenic acid which is an essential fatty acid which is considered to lower blood cholesterol.
Hardy zones 4 to 8 in full sun to partial shade on well drained or gravelly soil. Propagation is easy from seed and it often self seeds. Pest and disease resistant.

* photo taken on Aug 4 2013 in Bayfield, Ontario

* photo taken on Aug 25 2013 @ University of Maryland, College Park

* photos taken on Aug 17 2014 in Columbia, MD

* photo taken Aug 2016 @ Patuxent Research Refuge, Laurel, MD

* photo taken on July 26 2023 in Columbia, MD

* photo taken on Aug 16 2024 in Bayfield, ON

Oenothera brevipes ( Desert Primrose )

Oenothera caespitosa ( Tufted Evening Primrose )
A fast growing, rhizome spreading, tufted, evergreen perennial, reaching a maximum size of 10 inches x 2 feet, that is native to western North America ( from Washington State to southeast Alberta to southern Manitoba; south to southern California to western Texas ). It is endangered in Washington State, Saskatchewan and Manitoba. It is found on dry hills in the wild. Desert Primrose can be invasive on some sandier sites.
The coarsely-toothed, oblanceolate leaves are up to 6 x 0.8 inches in size. The foliage appears from the ground rather than on a stem. The foliage is blue-gray.
The fragrant, white ( later fading to pink ) flowers, up to 4 inches across, are borne on short stems during the summer.
The flowers open during the evening.
Hardy zones 3 to 8 in full sun on light, sandy, dry soil. Hates winter wetness.

Oenothera californica ( California Evening Primrose )
A rhizomatous, low, spreading perennial, reaching up to 5 inches tall, that is native to the southwestern U.S. ( from central California to central Nevada to southwestern Utah; south to the Baja Peninsula to central Arizona ). It eventually forms large clumps ( up to 10 feet across ).
The deeply-cut, narrow, lance-shaped leaves, up to 2.3 inches long, are silvery-gray.
The flowers, up to 2 inches wide, are white.
Hardy zones 6 to 9 in full sun on sandy, well drained soil. It is extremely heat and drought tolerant.

* photo taken by Jean Pawek @ CalPhotos

var. eurekensis ( Eureka Dunes Evening Primrose )

* photo taken by Drew Kaiser

Oenothera 'Cold Crick'
A hybrid with Oenthera fruitcosa parentage. A fast growing, dense, long-lived, clumping perennial, reaching 1 x 1.5 feet.
The deep green, narrow foliage turns to intense orange-red during autumn. The stems are reddish.
The very abundant, glowing bright yellow flowers on late spring to early summer. It usually blooms for 6 or more weeks and does not produce seed, therefore it is not invasive.
Hardy zones 5 to 8 in full sun to partial shade on fertile, well drained soil. Deer resistant. Cut back by 1/2 after blooming. It can be propagated from cuttings or by division during early spring.

Oenothera fremontii ( Fremont's Evening Primrose )
A perennial, native to Nebraska and Kansas. Hardy zones 4 to 9 in full sun to partial shade on well drained soil.

* USDA-NRCS PLANTS Database

'Lemon Silver'
Forms a low, spreading mat, reaching a maximum size of 8 inches x 2 feet.
The non-toothed, long, silvery foliage contrasts with large, pale yellow flowers, up to 3 + inches across, that are borne early summer to early autumn.

* photo taken on May 18 2013 in Columbia, MD

* photo taken on Sep 26 2013 in Baltimore Co., MD

'Shimmer'
Moderate growing, low and spreading in habit, reaching up to 4 x 10 inches in one year, eventually up to 0.8 x 2 feet.
The very narrow, fine-textured linear leaves are up to 4 inches in length. The foliage is silvery-gray.
The bright yellow flowers, up to 3 inches across, are borne late spring through early autumn.

* photo taken on 2012 in Columbia, MD

* photo taken on June 10 2013 in Columbia, MD

* photo taken on Oct 22 2014 @ Historic London Town, Edgewater, MD

* patent photo

Oenothera fruticosa ( Common Sundrops )
A long-lived, clumping perennial, reaching a maximum size of 5.3 x 6 ( rarely over 3 x 4 ) feet, that is native to North America ( Missouri to Massachusetts; south to Louisiana to northern Florida ). Spreads by underground roots to form large stands.
The toothed, narrowly-oblong leaves, up to 4.5 inches in length, are deep green.
The yellow flowers, up to 2.3 inches across, are borne during late spring into summer ( sometimes repeating into early autumn ) and are open during the daytime only.
Hardy zones 2 to 9 in full sun to partial shade on very well drained soil.
It is very drought tolerant. Divide every 2 to 3 years during early spring to maintain vigor.

* photos taken on May 16 2011 in Washington, D.C.


* photos taken on June 6 2012 in Columbia, MD
* photo taken @ U.S. Botanical Garden, Wash., DC on Aug 25 2014

* photo taken on June 9 2015 in Columbia, MD

* photos taken on May 27 2017 @ Meadowlark Botanical Gardens, Vienna, VA

* photo taken on Jun 20 2016 in Columbia, MD

* photos taken on June 3 2017 in Columbia, MD

* photo taken on Feb 2 2018 in Columbia, MD

* photos taken on May 28 2019 in Columbia, MD

* photos taken on June 8 2021 in Columbia, MD

* photos taken on June 1 2022 in Columbia, MD

* photos taken on June 7 2023 in Columbia, MD

'Fireworks'
Reaches a maximum size of 5.5 x 6 ( rarely over 3 x 4 ) feet, with red stems and yellow flowers, up to 3 inches across, borne early to mid summer.
The foliage often turns to glowing red during autumn.

* photo taken on June 10 2013 in Columbia, MD


'Highlight'
Upright in habit, reaching up to 15 inches, with lightly fragrant, bright yellow borne all summer long.

'Lapsley'
Reaches a maximum size of 1.5 feet, with large, yellow flowers borne all summer long.

'Summer Solstice'
Reaches a maximum size of 2 x 4 feet, with foliage that turns bright red during summer, then to deep burgundy red during autumn.
The bright yellow flowers are borne from early summer to early autumn.

'Yellow River'
Reaches up to 1.5 x 2+ feet, with green stems and yellow flowers, up to 3 inches across.
The foliage turns to reddish-purple during autumn.

Oenothera hookerii ( Hooker's Evening Primrose )
A perennial, natve from Washington State to Montana to Kansas; south to Mexico.

* photo taken by Joe F. Duft @ USDA NRCS. 1992. Western wetland flora

Oenothera howardii ( Bronze Evening Primrose )
A biennial, reaching up to 4 feet in height, that is native from Nevada to Kansas.
The hairy, wavy-edged, narrowly lance-shaped leaves are gray-green.
The large, yellow flowers are borne all summer long.
Hardy zones 4 to 9 in full sun on sandy or gravelly, well drained soil.

Oenothera kunthiana ( Kunch Sundrop )
A moderate growing perennial, reaching up to 1.3 x 1 foot, that is native to western and central Texas.
The lance-shaped leaves are deep green.
The pink or rarely white flowers are borne all summer long, lasting into autumn. They open during the morning.
Hardy zones 6 to 9 ( 5 on protected sites ) in full sun on well drained soil. It is very drought tolerant.

'Glowing Magenta'
Intense deep pink flowers, otherwise identical to species.

* photos taken on 2012 in Columbia, MD

* photo taken on May 20 2017 in Pikesville, MD

Oenothera lamarckiana
A perennial, reaching a maximum height of 3 feet.
The yellow flowers are up to 4 inches across.
Hardy zones 4 to 8

Oenothera 'Lemon Drops'
A low, spreading, rhizomatous, groundcover perennial, reaching up to 21 inches x 3 feet. The attractive foliage is deep green. The bright yellow flowers, up to 1 inch across, are borne all summer long. It does not set seed so it does not self seed or require deadheading. Hardy zones 5 to 9 in full sun to partial shade on well drained soil. It is heat, drought and poor soil tolerant.

* photos taken on June 4 2012 in Columbia, MD
* photos taken on Oct 21 2014 @ U.S. Botanical Gardens, Washington, DC

* photo taken on June 16 2015 in Columbia, MD

* photo taken on Jun 20 2016 in Columbia, MD

Oenothera macrocarpa ( Missouri Evening Primrose )
Also called Ozark Sundrops. A fast growing, long lived, deep rooted, mat-forming, prostrate, spreading perennial, reaching a maximum size of 2 x 4 ( rarely over 1 ) feet, that is native to south central U.S. The Missouri Evening Primrose forms a massive underground tuber in order to preserve moisture during drought. It looks great cascading over retaining walls.
The narrow leaves, up to 6 inches in length, are glossy deep green.
The showy, huge, bright yellow flowers, up to 6 ( rarely over 4 ) inches across, that open during the afternoon and close the next morning. The flowers are borne late spring to mid-autumn.
Hardy zones 3 to 8 in full sun on deep, light, well drained soil. Very drought tolerant, it does tolerate clay if not waterlogged. Deer resistant and attracts butterflies.

* photos taken on Aug 1 2013 in Stratford, Ontario

'Comanche Campfire'
Reaches up to 16 inches x 2 feet, with silvery foliage and bright yellow flowers borne over a long season.
Hardy zones 4 to 9, it originated in western Oklahoma and is very heat tolerant.

supsp. 'incana'
Reaches a maximum height of 8 inches, with silvery-gray foliage and large, golden-yellow flowers borne on red stems.
subsp 'oklahomensis'

* photo taken by Clarence A. Rechenthin @ USDA-NRCS PLANTS Database

'Silver Blade'
A groundcover perennial, reaching only 8 inches x 3 feet, with silver-gray foliage.

Oenothera missouriensis ( Ozark Sundrops )
Also called Missouri Primrose. A fast growing, prostrate, mat-forming perennial, reaching a maximum size of 2 x 4 feet, that is native to the south central U.S. ( Kansas to Missouri; south to Texas ).
The narrow leaves, up to 6 inches in length, are deep green.
The pale yellow flowers, up to 6 inches across, are borne on short stems from late spring to mid-autumn. The flowers open during the evening.
Hardy zones 3 to 8 in full sun to partial shade on very well drained soil. Extremely drought tolerant. Does not like extreme heat when combined with humidity and will actually do better in cooler summer maritime climates.

* photo taken on June 22 2014 in Howard Co., MD

Oenothera nuttallii ( Nuttall's Sundrop )
A long-lived, rhizomatous perennial, reaching up to 3.3 x 2 feet in size, that is native to sandy prairie in central North America ( from near Red Deer, Alberta to southern Saskatchewan to western Ontario; south to Wyoming to Colorado to northern Kansas.
The narrow oblong leaves, up to 3 x 0.2 inches in size, are dull green above, downy white beneath.
The white ( fading to pink ) flowers, up to 1.8 inches wide, are borne all summer long.
The stems are whitish.
Hardy zones 3 to 7 in full sun on sandy or very well drained soil. Propagation is from seed sown during early spring.

Oenothera perennis ( Dwarf Sundrops )
A fast growing to invasive spreading, neat, tufted perennial, reaching a maximum size of 2 feet x 32 inches. It is native as far north as Kenora to Chapleau to Killarney in Ontario as well as in southeastern Quebec to Cape Breton, Nova Scotia. It is found on sandy lakeshores in the wild.
The smooth-edged, lance-shaped leaves are up to 2.3 inches in length.
The yellow, cup-shaped flowers, up to 1 inch across, are borne on leafy spikes all summer long. The flowers open during the daytime.
Hardy zones 4 to 9 in full sun on dry to moderately moist, well drained or gravelly soil.

Oenothera pilosella ( Pilosella Sundrops )
A noninvasive perennial, reaching a maximum height of 2.4 x 2.4 feet, that is native to the central U.S. ( from central Iowa to central Wisconsin to central Michigan to Sauble Beach and Oliphant, Ontario to northern New York State to Maine; south to Louisiana to far northern Alabama to Virginia ). It is endangered in Ontario and West Virginia. It is found on sandy shorelines in the wild.
The attractive mid-green foliage turns red during autumn.
The golden-yellow flowers, up to 2 inches wide, are borne profusely during late spring then occasionally during summer.
Hardy zones 3 to 8 in full sun to partial shade on well drained soil. It is clay tolerant despite often being found on sand dunes in the wild.

* photo taken by Robert H. Mohlenbrock @ USDA SCS. 1989. Midwest wetland flora

* USDA-NRCS PLANTS Database / USDA NRCS. Wetland flora

Oenothera rosea ( Rose Evening Primrose )
A perennial, reaching up to 2.2 ( rarely over 1 ) in height, that is native from southern Arizona to central Texas; south into Mexico.
The toothed or lobed, oblong leaves, up to 2.5 x 1 inches in size, are mid-green. It bears fragrant, soft pink flowers, up to 0.8 inches wide, are borne early summer to early autumn.
Hardy zones 6 to 9 in full sun on very well drained soil, it is tolerant of extreme heat. It is propagated from seed.

Oenothera speciosa ( Pink Sundrops )
A fast spreading to invasive, rhizomatous perennial, reaching a maximum height of 20 ( rarely over 10 ) inches, that is native to the south central U.S. ( from Kansas to Missouri; south to Texas ). It can be used as a groundcover on large sites and can even be mowed on occasion. Individual plants can spread to 3 feet or sometimes more.
The toothed, narrow-oblong leaves are up to 3.5 x 1.3 inches in size. The mid-green foliage turns to deep red during autumn.
The white ( aging to deep pink ), cup-shaped flowers, up to 3 ( rarely over 2 ) inches across, are borne late spring lasting into early autumn. The flowers attract hummingbirds and butterflies.
The flowers are open during the daytime, unlike many related species that bloom during evening and night.
Hardy zones 5 to 8 ( 4 on protected sites ) in full sun to partial shade. It is easy to grow in hot summer regions and will even grow in dry partial shade with dense tree roots ( a good idea, it may be slightly less invasive there ). Very heat and drought tolerant, even thriving against south facing walls and in parking lot islands. Deer resistant.
Planting in containers will keep this plant contained.

'Twilight'
Reaches up to 1 foot in height, with very attractive foliage that is deep purple-bronze and bordered in mid-green.
The abundant, large, pink flowers are borne all summer long.

* photos taken on Apr 26 2019 in Elkridge, MD

Oenothera tetragona ( Narrowleaf Evening Primrose )
Also called Oenothera fruticosa subsp glauca. A fast spreading to invasive perennial, reaching a maximum size of 5.5 x 5 ( rarely over 3 ) feet, that is native to eastern North America ( from Manitoba to Nova Scotia; south to Alabama to South Carolina ).
The smooth-edged, oblanceolate leaves, up to 8 x 0.3 ( rarely over 4 ) inches in length, are red tinted at first, turning to deep green. The foliage often turns to red by late summer. The foliage is borne on red stems.
The lightly fragrant, silky, bright yellow, cup-shaped flowers, up to 2 inches across, are borne mid to late summer. The flowers are open during the daytime.
Hardy zones 3 to 8 in full sun to partial shade.

* USDA-NRCS PLANTS Database

* photos taken on June 16 2015 in Columbia, MD

var 'cinaeus'
Foliage is bronze during spring. The large flowers are deep yellow.

var. 'fraseri'
Blue-green foliage and large flowers, up to 2 inches across.

var 'riparia'
Dwarf in habit, reaching up to 8 x 16 inches. Great for rock gardens.