Oenothera biennis | ‘Evening Primrose’, ‘Evening Star’, ‘Sundrop’ | ~ 100 seeds
Native to North America (and widely naturalised elsewhere), Oenothera biennis is a flowering herbaceous biennial of the family Onagraceae which makes a wonderful addition to any garden!
Growing erect, green (often with reddish patches) stems to roughly two metres in height, biennis‘ lance-shaped leaves reach up to approximately twenty centimetres long by two and a half centimetres wide. Sweet-smelling, bright yellow hermaphrodite flowers appear almost continuously between late spring and autumn, although generally only in the early morning or evening. Comprising of four petals, these blooms are up to roughly five centimetres in diameter.
‘Evening Primrose’ has been cultivated as an edible, medicinal and ornamental plant for many hundreds of years. Almost every part of the plant is useful for something, including the flowers, leaves, roots and seeds (the latter being a good source of several essential amino acids). Traditionally, the species has been used to treat all sorts of illnesses, such as asthma, high blood-pressure, skin complaints and whooping cough. It’s known to be potentially harmful if ingested by sufferers of epilepsy. Commercially, Oenothera biennis is grown for its valuable ‘Evening Primrose Oil’ (often sold as a dietary or other supplement). Its seed is an important source of nourishment for many bird species too.
The popularity of this useful species over the years has earned it many synonyms, including Brunyera biennis, Oenothera chicaginensis, Oenothera chicagoensis, Oenothera grandiflora, Oenothera muricata, Oenothera pycnocarpa, Oenothera renneri, Oenothera rubricaulis, Oenothera stenopetala, Oenothera suaveolens, Onagra biennis and Onagra muricata. Consequently, biennis has also garnered a rich variety of informal names too (besides ‘Evening Primrose’), such as ‘Common Evening Primrose’, ‘Evening Star’, ‘Fever-plant’, ‘German Rampion’, ‘Hoary Evening Primrose’, ‘Hog Weed’, ‘King’s Cure-all’, ‘Night Willow-herb’, ‘Sundrop’ and ‘Weedy Evening Primrose’.
It’s quite easy to grow from seed in USDA Hardiness Zones 5-8 (so much so as to be considered invasive in some regions), preferring loamy soil in a dry, sunny habitat less than seven hundred metres above sea level. This species requires light to germinate, so sow the seeds approximately five millimetres to one centimetre below the surface of some mildly acidic to mildly alkaline, well-drained soil. Germination usually takes somewhere between two to four weeks, climate-dependent. Once the young plants are hardy enough, transplant them to larger containers or the ground, spacing them a minimum of thirty centimetres apart somewhere in full sun.
All the seed sold by Arkham’s Botanical was freshly and ethically sourced