Evening primrose relates to several plants in the Oenothera genus. There are many kinds of this plant around the world, but the most common one in the UK is Oenothera biennis, a North American biennial plant that has spread here. Pollinators that fly at night, like moths, are drawn to its big, bowl-shaped, light yellow flowers that open in the evening. In ancient times, Oenothera biennis was used to treat baldness and pain. Today, it’s used to make evening primrose oil, which is said to help balance hormones and ease the stress of menopause and premenstrual syndrome. Evening primrose is edible to both humans and other animals.
In the garden, evening primrose releases a pleasant evening fragrance, and is a good wildlife plant. They come in a number of different varieties with blooms that appear during the day, such as orange and apricot ones.
Evening primrose is a plant that often sparks debates among gardeners. Is it a perennial or an annual? Is it a flower or a weed? While its classification may be up for discussion, one thing is certain – evening primrose is a beautiful plant with some amazing benefits. In this article, we’ll take a deep dive into evening primrose to uncover its perennial status growing habits, and uses.
An Overview of Evening Primrose
Evening primrose refers to flowering plants in the genus Oenothera, including around 145 different species. Most commonly grown is the common evening primrose (Oenothera biennis). This plant is native to North America but has naturalized in other parts of the world.
Evening primrose is known for its eye-catching yellow blooms that open in the evening The flowers emit a delicate, lemon scent and close up during the day. They bloom from mid-summer to fall on tall flower spikes
Below the flowers is a basal rosette of oblong leaves with a reddish tint. The plant can grow quite tall, reaching heights of 3 to 5 feet. When happy, evening primrose will self-seed freely.
Is Evening Primrose a Perennial?
Here’s where things get tricky. Evening primrose is often classified as a biennial. This means the plant has a two-year life cycle. During the first year, it forms a basal rosette. It blooms, sets seed and dies back in year two.
However, since evening primrose self-seeds so readily, new plants constantly emerge. So you’ll likely have evening primroses returning year after year. For this reason, many gardeners consider evening primrose a perennial. It persists in the garden even though individual plants are short-lived.
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Botanically, evening primrose is classified as a biennial.
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Horticulturally, it behaves as a self-seeding perennial.
No matter how you classify it, with proper care you can enjoy evening primrose for many seasons in your garden.
Growing Evening Primrose from Seed
Evening primrose is easily grown from seed. In fact, planting seeds is the preferred method since mature plants dislike transplanting.
There are a couple approaches to sowing evening primrose:
Sow in late fall. The seeds need exposure to cold, moist conditions to break dormancy. Sow seeds in late fall so they stratify over winter. The plants will emerge in spring and flower the following summer. This mimics their natural life cycle.
Sow in early spring. You can also sow seeds in early spring indoors. Use peat pots and keep them chilled in the fridge for 4-6 weeks before moving to a sunny spot. Transplant outside after the last frost.
Space plants 12-18 inches apart in full sun to partial shade. They prefer slightly acidic, well-drained soil but will adapt to most conditions. Water when the soil dries out to the touch.
Caring for Evening Primrose
Luckily, evening primrose isn’t fussy once established. Here are a few tips for care:
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Provide full sun for the most prolific flowering. At least 6 hours of direct sun is recommended.
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Water 1-2 times per week, allowing the soil to dry slightly between waterings.
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Remove spent blooms to encourage more flowers.
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Cut plants back to 6 inches after flowering finishes in fall.
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Mulch plants in cold winter areas for added insulation.
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Divide large clumps every 2-3 years to rejuvenate.
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Pull unwanted seedlings to control spread.
Common Problems with Evening Primrose
While evening primrose is hardy, a few issues can arise:
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Mildew – Powdery white fungal infection. Improve air circulation and avoid wet foliage.
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Rust – Reddish fungal spots on leaves and stems. Remove and destroy affected plants.
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Root rot – Caused by overwatering. Allow soil to dry between waterings.
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Self-seeding – Clip spent blooms and pull unwanted seedlings to control spread.
Aside from these problems, deer, rabbits, and rodents may nibble on evening primrose. Using animal deterrents can help protect plants.
Uses for Evening Primrose
Aside from being a beautiful plant, evening primrose has some excellent benefits:
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The leaves are edible and can be added to salads or cooked like spinach. They have a slight peppery flavor.
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The plant has a long history of medicinal use, dating back to ancient times. The leaves and roots were used to treat inflammation, headaches, and digestive issues.
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Today the seeds are cold pressed to produce evening primrose oil. This popular supplement is taken to manage PMS, menopause, and skin conditions like eczema.
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Evening primrose attracts pollinators to the garden, like moths, beetles, and hummingbirds.
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The vibrant yellow blooms add cheery color to any garden. They work beautifully in wildflower meadows, cottage gardens, borders, and cutting gardens.
So while its perennial status may be hazy, there’s no denying evening primrose is a valuable plant! A few self-sown plants can provide beauty, medicine, food, and ecosystem support for years to come. With its benefits and easy care, evening primrose is welcome in both perennial and annual gardens.
Where to grow evening primrose
Though it only grows to about 1 m tall, evening primrose does best in full sun to partial shade and moist but well-drained soil. Plant it in the middle or back of your border.
Varieties of evening primrose to grow
Flowers age from pale yellow to apricot and then coral pink. Height x Spread: 1m x 40cm
Soft yellow flowers with a beautiful evening fragrance. H x S: 1m x 60cm
Evening Primrose (Oenothera Speciosa) | 2 Reasons Not to Grow
FAQ
Does evening primrose come back?
Do evening primroses like sun or shade?
Does primrose come back every year?
Do evening primroses spread?
Can evening primrose grow in shade?
Evening primrose is one of the easiest plants you can grow in your garden. It prefers full sun but can grow in slight shade too. The biggest factor is to make sure it’s planted where the soil is well-draining. You should aim to provide the highest quality soil possible, but this plant is so versatile it can even grow in subpar soil.
How tall does evening primrose grow?
Getty Images Evening primrose can grow to an average height of around 1m, so plant it towards the middle or back of your border, in full sun to partial shade, and in moist but well-drained soil. The best way to grow evening primrose is from seed.
Can evening primrose grow in the UK?
All you need to know about growing the evening primrose wildflower, in our Grow Guide. Evening primrose relates to several plants in the Oenothera genus. There are many varieties worldwide but the most common in the UK is Oenothera biennis, a biennial plant native to North America, which has naturalised here in the UK.
Is evening primrose a perennial?
Evening primrose (genus Oenothera) features cupped flowers in sunny yellows, moony whites, and soft pinks. It comes from a family of flowering plants—many native to North America—that behave as perennials, biennials, or annuals depending on the variety and climate.