Evening primrose: growth, care & benefit

With its beautiful flowers, one cannot oversee the common evening primrose in a garden. In this article, you will learn what to consider when growing evening primrose and how to use it.

Common evening primroses (Oenothera biennis) unravel their beauty at night. The bright yellow blossoms open at dusk and shine in the dark. But no worries the flowers will stay open to greet you in the morning.

Evening primrose: origin and characteristics

Although it seems like the common evening primrose fits perfectly into Europe’s native flora it is actually from North America and has only been around since the 17^th century. Brought as an ornamental plant, the flowers soon left borders and fences behind and spread throughout Europe. So did others of the genus Oenothera creating cross-breeds which is why we have numerous evening primrose species in Europe today.

The common evening primrose is by no means inconspicuous. It usually grows between 80 and 180 centimetres tall sticking out well above many of its leafy neighbours. Underground, things are no different, its fleshy taproot can grow as deep as the plant is tall. In the first year, however, none of that is apparent yet. The lance-shaped leaves start off on the ground arranged in rosettes and only in the following year the main shoot sprouts, with a long inflorescence appearing at its tip from June onwards. The bright yellow and sweet-scented flowers bloom gradually from bottom to top. They attract numerous species of hawk moths as well as many other species of moths and butterflies. Among them is the hummingbird hawk moth (Macroglossum stellatarum), which is especially lovely and indeed looks like a hummingbird when it flies.

The most beautiful species

The common evening primrose is just one among many relatives of its genus. In total there are about 200 species of the genus Oenothera, 30 of which also grow in Europe. Oenothera biennis is the most popular one but we collected further varieties for you that might sound interesting:

• Large-flowered evening primrose (Oenothera glazioviana): This variety is widespread; reaching a height of up to 2 metres. Its flowers are slightly larger than those of the other evening primroses. The red buds and red dotted stem make the main difference though.
• Narrow-leaved sundrop or narrowleaf evening primrose (Oenothera fruticosa/Oenothera tetragona): The flowers are similar to the typical evening primrose look – shining yellow, however it is not straight and upright but rather branchy. The flower stems of narrow-leaved sundrops reach heights of up to 70 cm.
• Pinklady or pink evening primrose (Oenothera speciosa): Very different appearance: It grows to be more wide than tall. Its maximum size is 30 cm. The flowers go from whitish to pink. Unfortunately, this species is difficult to control and spreads easily.
• Bigfruit evening primrose or Missouri evening primrose (Oenothera macrocarpa): This species does not grow taller than 30 cm and is perfect for planting in rock or alpine gardens. It forms a dense and lush carpet of yellow flowers.

Planting evening primrose

You can buy evening primrose either as a young plant or as seeds. Potted plants can be planted out from spring until summer. The plants are hardy, but should not be exposed to frost too soon, as they were most-likely grown in a greenhouse.

The perfect location

Although evening primrose is incredibly diverse, all species found in Europe somehow prefer the same thing. Outside of gardens and plantations, wild evening primroses are to be found where other plants have a hard time growing. The plant grows on gravel banks, railway embankments and wasteland as well as old quarries. They prefer sandy and nutrient-poor soil, ideally including lime. Of course, sunshine is crucial for evening primroses. They can cope with partial shade as well. Most importantly, the location for evening primroses needs to be dry in winter.

How to plant evening primrose

You can grow your evening primrose in a pot as well as out in the open air. If you plant several plants, make sure to leave enough distance between individual plants especially with large varieties 30 centimetres planting distance is advisable. This keeps the plant well aerated and less prone to.

Since evening primroses have long roots, choose a deep flower pot when planting them in containers. The substrate can consist of sand for the most part just mix 30% to 50% of sand into your usual garden soil. 

• Choose a deep planter
• For substrate, mix garden soil with at least 30 % of sand
• Keep the planting distance in the garden bed (at least 30 cm between plants)

Tips for evening primrose care

Evening primroses are extremely resistant. They did not spread throughout Europe on their own for nothing. In any case, the plants do not need fertiliser. And you can spare yourself the watering, because the plant doesn’t mind even long periods of drought. One step that we recommend not skipping when it comes to evening primrose plant care is pruning. A vigorous pruning in autumn or towards the end of winter stimulates early flowering.

Propagation

Evening primroses produce an incredible number of very small seeds. For this reason, if you don’t want to find this rapidly reproducing plant all over the garden, don’t throw the cut flowers on the compost.

Sowing evening primrose is very easy. If you want the plant to grow as an annual, we recommend sowing at the end of April or beginning of May. Evening primroses sown in July or August will not flower until next year.

When sowing remember that evening primrose seeds require light to germinate. Therefore, do not cover the seeds with soil at all or dust them lightly with some soil on top. After about 12 to 16 days the first seedlings will appear.

Once the plant is established and allowed to ripen, it will produce seeds and reliably provide you with offspring.

Summary: Propagating evening primrose

• Evening primroses produce plenty of seeds
• Sow in April/May or July/August
• Seeds require light to germinate

Are evening primroses poisonous?

Evening primrose is not poisonous at all. On the contrary: with common evening primrose all of the plant parts are edible. The plant can also be used in various ways for natural medicine, which we will explain in the following.

Evening primrose: use and benefits

Evening primroses provide eye-catching spots of colour in your perennial garden bed, but they also attract various insects, such as moths, butterflies and bumblebees. It makes an excellent source of food for butterflies and many other insects.

However, it is not only delicious to insects. You too can enjoy the plant with all your senses. The fleshy taproot, for example, can be harvested in autumn and prepared as a delicious root vegetable. In spring, the fresh leaves are ideal for salads. The highlights are the edible, bright yellow flowers, which can decorate all sorts of dishes in summer. The flowers look gorgeous in home-made ice cubes, which will make lemonades or cocktails even more special.

And evening primrose has even more to offer. The oil from its seeds has a soothing and anti-inflammatory effect on irritated skin. You can treat dandruff, dry skin and even neurodermatitis. And not to forget, evening primrose oil is part of many natural cosmetic products.

Tea made from dried evening primrose leaves can counteract stomach and digestive problems. It will also help calm mood swings, moodiness and other signs that many people experience before their period.