North America Native Plant

Oklahoma Evening Primrose

Botanical name: Oenothera macrocarpa oklahomensis

USDA symbol: OEMAO2

Life cycle: perennial

Habit: forb

Native status: Native to the lower 48 states  

Synonyms: Megapterium oklahomense J.B.S. Norton (MEOK)  âš˜  Oenothera macrocarpa Nutt. var. oklahomensis (J.B.S. Norton) Reveal (OEMAO)  âš˜  Oenothera missouriensis Sims var. oklahomensis (J.B.S. Norton) Munz (OEMIO2)   

Oklahoma Evening Primrose: A Prairie Beauty for Your Garden If you’re looking for a native wildflower that can handle tough conditions while putting on a spectacular show, meet the Oklahoma evening primrose (Oenothera macrocarpa oklahomensis). This hardy prairie native brings bright yellow blooms and silvery foliage to gardens across the ...

Rare plant alert!

Region: Conservation status by state

Status: S5T3?: Status is uncertain but is somewhere between the following rankings: Inexact rank: ⚘ Subspecies or variety is vulnerable: Either very rare and local throughout its range, found only in a restricted range (even if abundant at some locations), or factors are making it vulnerable to extinction. Typically 21 to 100 occurrences or between 3,000 and 10,000 individuals. ⚘ Secure: At very low or no risk of extinction in the jurisdiction due to a very extensive range, abundant populations or occurrences, with little to no concern from declines or threats. ⚘

Oklahoma Evening Primrose: A Prairie Beauty for Your Garden

If you’re looking for a native wildflower that can handle tough conditions while putting on a spectacular show, meet the Oklahoma evening primrose (Oenothera macrocarpa oklahomensis). This hardy prairie native brings bright yellow blooms and silvery foliage to gardens across the south-central United States, proving that native plants can be both beautiful and practical.

What Is Oklahoma Evening Primrose?

Oklahoma evening primrose is a perennial forb – basically a non-woody flowering plant that comes back year after year. Unlike its woody shrub neighbors, this plant stays low to the ground with soft stems and leaves, making it perfect for ground cover or front-of-border plantings.

You might also see this plant listed under several scientific synonyms, including Megapterium oklahomense or Oenothera missouriensis var. oklahomensis, but they’re all referring to the same delightful prairie wildflower.

Where Does It Call Home?

This native beauty naturally occurs across Kansas, Oklahoma, and Texas, thriving in the challenging conditions of the Great Plains. As a true native plant of the lower 48 states, it’s perfectly adapted to the climate swings and soil conditions of its home range.

Why Gardeners Love Oklahoma Evening Primrose

There are plenty of reasons to fall in love with this prairie charmer:

  • Stunning evening blooms: Large, bright yellow flowers open in the evening and night, creating a magical twilight garden experience
  • Drought champion: Once established, it handles dry conditions like a pro
  • Pollinator magnet: Night-flying moths, bees, and other beneficial insects flock to the blooms
  • Low maintenance: This is a plant-it-and-forget-it kind of perennial
  • Native plant benefits: Supports local ecosystems and wildlife

Perfect Garden Spots

Oklahoma evening primrose shines in several garden styles:

  • Prairie and wildflower gardens: Natural choice for native plant landscapes
  • Rock gardens: Thrives in well-draining, rocky conditions
  • Xeriscaping: Excellent for water-wise landscaping
  • Ground cover: Spreads to form attractive low carpets
  • Evening gardens: Perfect for spaces enjoyed at dusk

Growing Conditions and Care

The beauty of Oklahoma evening primrose lies in its simplicity. This tough native asks for very little:

Sunlight: Full sun is best – at least 6-8 hours of direct sunlight daily

Soil: Well-draining soil is crucial. It tolerates poor, sandy, or rocky soils but struggles in heavy clay or waterlogged conditions

Hardiness: Thrives in USDA zones 4-8, handling both cold winters and hot summers

Watering: Drought tolerant once established. Water regularly the first season, then let nature take over

Planting and Care Tips

Getting started with Oklahoma evening primrose is refreshingly straightforward:

  • Timing: Plant in spring after the last frost or in early fall
  • Spacing: Give plants room to spread – they’ll naturally form colonies
  • Maintenance: Cut back spent foliage in late winter to make room for new growth
  • Propagation: Plants may self-seed in ideal conditions, creating natural colonies
  • Fertilizing: Generally unnecessary – these prairie natives prefer lean soils

Wildlife and Pollinator Benefits

Oklahoma evening primrose is more than just a pretty face. Its evening-opening flowers provide crucial nectar for night-flying pollinators, including sphinx moths and other beneficial insects. As a native plant, it also supports local food webs and provides habitat for wildlife that have evolved alongside it.

Is Oklahoma Evening Primrose Right for Your Garden?

This native wildflower is ideal if you’re looking for:

  • A low-maintenance, drought-tolerant perennial
  • Evening garden interest with fragrant night blooms
  • Native plant options for ecological gardening
  • Ground cover for challenging, dry sites
  • Plants that support local pollinators and wildlife

Oklahoma evening primrose proves that native plants can be both environmentally responsible and garden-worthy. With its bright blooms, drought tolerance, and wildlife benefits, it’s a wonderful addition to gardens across its native range. Give this prairie beauty a sunny, well-drained spot, and it’ll reward you with years of evening magic.

Oklahoma Evening Primrose

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Rosidae

Order

Myrtales

Family

Onagraceae Juss. - Evening Primrose family

Genus

Oenothera L. - evening primrose

Species

Oenothera macrocarpa Nutt. - bigfruit evening primrose

Plant data source: USDA, NRCS 2025. The PLANTS Database. https://plants.usda.gov,. 2/25/2025. National Plant Data Team, Greensboro, NC USA