Everyone has seen those tall weeds with long narrow leaves and covered with cup-shaped yellow flowers. Sometimes they can grow to be five feet tall. For foragers and herbalists, it has a bounty of uses.
The plant in question is evening primrose (Oenothera biennis). Most people consider it a weed as it grows along roadsides and in waste places. Some consider it a wildflower. Evening primrose is a common pasture plant, and it thrives in open fields.
This herbaceous plant is classified as a biennial. Other closely related species can be annual or perennial. They can have pink, white or lavender colored flowers. Each individual bloom lasts only a day or two, but they are prolific and blossom in summer and early fall. Flowers tend to open more in the late afternoon, hence the name.
Biennial evening primrose produces only foliage and thick roots in its first season. In the second year the plant flowers. The thick fleshy roots can be cooked and eaten like potatoes. Roots become fibrous as the second season progresses.
Evening primrose roots remind me a little of parsnips. In early spring of their second year they develop a sweeter flavor like parsnips do. Cold temperatures are partially responsible for converting some of the starches to sugars.
Roots aren’t the only palatable part. All parts of the plant are edible, even the seeds. Some people utilize young leaves as cooked greens.
Others like to make tea from the flowers. Flowers can also be used in salads. Hummingbirds and other pollinators like them too. Plants are high in natural linolenic acid, an essential fatty acid often referred to as Omega-6.
Evening primrose grows best in well-drained soils. It tolerates a wide pH range and greatly benefits from large amounts of organic matter. Some gardeners like to domesticate it and plant it in their beds.
This one is aggressive, but like most other tap rooted plants it’s difficult to transplant. Once it gets established evening primrose can take over. It’s a prolific seed producer and the thick roots can crowd other plants. However, being a native plant makes it attractive for many people.
In recent years several companies have harvested seeds and pressed them to make evening primrose oil. This oil is often used to treat eczema and acne. For women it is used to ease PMS symptoms and menstrual breast pain. During menopause it’s often used to minimize hot flashes.
Some herbalists prescribe evening primrose oil to help reduce high blood pressure and improve overall heart health. Evening primrose oil is also recommended to reduce diabetic nerve pain. Anti-inflammatory properties of this oil also contribute to its use to treat the bone pain of rheumatoid arthritis.
Taking evening primrose preparations could be a problem for those taking blood thinners. Evening primrose oil does the same thing and results can be magnified. For people who experience seizures, evening primrose oil could make them worse.
As with any herbal medicine, always consult with your medical professional before embarking on any treatment. Natural herbal medicines are not automatically safe. Read and ask questions.
Ted Manzer teaches agriculture at Northeastern High School.