Surprising to many, pink evening primrose, Oenothera speciosa, is native to much of the United States. It is also called pink ladies, showy primrose, and a slew of other names. Pink evening primrose is very easy to grow, to the point where it can become aggressive in many gardens.
Oenothera speciosa is a sprawling and casual plant, at home in cottage gardens or naturalized settings.
It grows a couple of feet tall and blooms from May to July. Evening primroses open their flowers in the evening, but pink evening primrose opens in the morning in our climate (zone 8 – Georgia).
It is winter hardy to zone 4, and in its northern limit Oenothera speciosa blooms in the evening.
Pink evening primrose is drought-tolerant, making it a good choice for xeric gardens. Oenothera speciosa thrives in poor soils. In the neighborhoods of cities across its native range pink evening primrose seems to do a fine job of colonizing abandoned places. Well-drained soil is highly recommended. Oenothera speciosa can handle dry, but not wet.
Pink evening primrose is native and potentially invasive.
It is a prolific self-seeder. Oenothera speciosa spreads by rhizomes as well. It is a solid choice for a wildflower or meadow garden. Plant it where you will not mind colonization and spread.
Many gardeners regret planting it in their landscapes because once it gets established evening primrose can be tough to keep in bounds. If you are the type of gardener not comfortable with plants with wayward ways, consider avoiding primrose.
Still, it is a charming plant, and I am always happy to see it in neighborhood gardens in spring. One thing I have noticed is it is prevalent in the landscape some years more than others.