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I really love looking for wild plants that can be eaten or used as medicine, and evening primrose (Oenothera biennis) is one of my favorites. Foraging for this wonderful plant is always a highlight of my foraging season. Not only is it widely distributed throughout the U. S. But you can eat every part of the plant, and evening primrose is known to have healing properties.
Finding a new patch of evening primrose and carefully gathering its roots, leaves, flowers, and seeds gives me a rush of excitement. I know that I’m not only giving myself tasty and healthy food, but also natural remedies that have been used for hundreds of years. There is something truly magical about getting food and healing in the wild. Looking for evening primrose is a great example of this.
Evening primroses are a beautiful addition to any garden with their bright, colorful blooms that open in the evening. An added bonus is that allowing some flowers to go to seed provides an ample supply of evening primrose seeds you can collect for future plantings or to share with gardening friends.
In this article, we’ll cover when and how to harvest evening primrose seeds so you can easily collect seeds from your plants.
An Overview of Evening Primroses
Evening primroses belong to the Onagraceae family and are known scientifically as Oenothera. They are native to North and South America but grown as ornamentals worldwide.
These herbaceous short-lived perennials produce colorful flowers in shades of white, pink, red and yellow. They open in the evening, hence the common name. Evening primroses are also called suncups, sundrops and moonflowers.
Popular evening primrose varieties include
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Large-flowered evening primrose (O. macrocarpa) – Yellow, 3-4 inches wide
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Ozark sundrops (O. missourensis) – Bright yellow, 2-3 inches wide
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Showy evening primrose (O. speciosa) – Pink, 2-3 inches wide
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Fragrant evening primrose (O. triloba) – Pale yellow, lightly fragrant
Evening primroses thrive in full sun and well-drained soil. Give them room to spread as mature plants can reach 2-6 feet tall and wide. They readily self-seed once established.
When to Harvest Evening Primrose Seeds
Timing is everything when it comes to collecting seeds. Harvest too early and the seeds may not be viable. Harvest too late and you risk losing the seeds.
For evening primroses, seeds should be harvested once the seed pods are completely dry and brown. This indicates the seeds are mature.
Check the pods regularly as they near maturity. The pods will change from green to yellowish, then light brown, and finally dark brown.
Start checking a few weeks after the flowers finish blooming. Gently squeeze pods to check for dryness. If you hear seeds rattling inside, they are likely ready for harvest.
In warmer climates, this is usually in mid to late summer. In cooler regions, it may be early fall before pods are dry enough.
Ideally harvest on a dry, sunny day. Morning is preferable to allow any residual moisture to evaporate.
How to Harvest Evening Primrose Seeds
Collecting evening primrose seeds is quick and easy. Here are two simple methods:
1. Cut Seed Pods
With this technique, use pruners or scissors to snip off the dried, browning seed pods directly from the plant.
Try to get as much of the stem attached to the pod as possible. This prevents seeds from scattering.
Place cut pods in a paper bag or envelope. Label with the variety and harvest date.
Once home, spread pods on newspaper or a screen to finish drying for 1-2 weeks. Break pods open and separate out the tiny, dark seeds. Discard pods and chaff.
2. Entire Mature Stalks
For a faster approach, simply cut off the entire faded flower stalk once pods are dry and brown.
Use pruners to cut the base of the stalk near the ground.
Gather several stalks together and secure with a rubber band or twine.
Hang the bundles upside down in a warm, dry spot to finish curing for 1-2 weeks.
Next, gently rub the stalks over a bucket to knock the seeds loose. Or, rub between your hands over a bowl to separate.
Storing Harvested Seeds
Once fully dry, place seeds in paper envelopes or resealable plastic bags. Label with details like variety and harvest date.
Store in an airtight container in a cool, dry location away from direct light. The refrigerator is ideal.
Kept dry and chilled, evening primrose seeds remain viable for 2-3 years before germination rates decline.
For best results, use harvested seeds within 1-2 years. Discard any that appear discolored, molded or damaged.
Tips for Maximizing Seed Production
Here are some useful tips to boost seed yields from your evening primroses:
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Grow different varieties apart to prevent cross-pollination
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Don’t deadhead spent blooms – allow some flowers to go to seed
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Stake tall varieties to prevent toppling under the weight of seed pods
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Remove competing weeds and irrigate during dry spells
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Cut back plant by 1/3 after initial bloom to encourage a second flush of flowers/pods
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Cover immature pods with breathable fabric to protect from heavy rain/wind
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Harvest seeds on a dry day to prevent molding
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Check plants daily as pods ripen to harvest at peak maturity
With proper timing and care, a few healthy evening primrose plants can produce abundant seeds for years to come.
When to Sow Harvested Evening Primrose Seeds
Evening primrose seeds need exposure to moist chilling, or stratification, in order to break dormancy and germinate well.
For spring planting, sow seeds outdoors in late fall or early winter. The natural cold, wet weather provides the stratification they need.
Or, sow in containers in late winter and set outdoors once overnight frost danger has passed.
You can also artificially stratify seeds by placing them between moist paper towels in the refrigerator for 4-6 weeks before planting.
Once sown, evening primrose seeds germinate best at soil temperatures of 60-70°F. Maintain even moisture – don’t allow soil to dry out.
Seedlings emerge in 10-20 days. Grow on indoors or in a sheltered spot outdoors. Harden off and transplant into the garden after all danger of frost.
How to Grow Evening Primroses from Seed
Here are some tips for successfully growing evening primroses from your saved seeds:
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Start seeds indoors 8-12 weeks before your last spring frost
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Sow seeds 1/8 inch deep in sterile seed starting mix. Cover lightly with vermiculite or soilless mix.
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Maintain a temperature of 65-70°F for best germination
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Keep seedlings moderately moist, misting often to prevent drying out
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Once sprouted, move to brighter light. Transplant seedlings when they reach 3-4 inches tall.
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Harden off before transferring to the garden after all chance of frost is past
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Space plants 12-18 inches apart in full sun and fertile, well-draining soil
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Water new transplants regularly until established
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Enjoy flowers the first year from early summer until fall
Storing Evening Primrose Seeds Long Term
For long term storage spanning several years, it’s best to keep evening primrose seeds in cold, dry conditions.
The optimal storage temperature is 35-41°F. Place packets inside resealable bags or glass jars in the refrigerator or freezer.
For very long term storage of 10 years or longer, consider cryogenic frozen storage. Seeds are frozen at -320°F in liquid nitrogen vapor.
Always use air tight, moisture proof containers for seed storage to prevent molding. Renew packets every few years to replenish seed moisture levels.
With proper harvesting techniques and favorable storage conditions, your evening primrose seeds will stay viable for many gardening seasons to come!
Where to find Evening Primrose
Evening primrose is a familiar sight to me, as I often find it growing near my home and on my homestead in eastern Connecticut. You’ve probably seen it too since it grows widely throughout the US. In fact, the USDA Forest Service reports that this plant can be found from Pennsylvania west to Nebraska, south to Texas then eastward to Florida. It is also known from Connecticut, New Mexico, Arizona, Utah, and California. It also occurs in northern Mexico. The native range is southern Missouri through the southeast and to the southwest.
The evening primrose is a true survivor and can thrive in a variety of environments. Based on my observations, I’ve learned that it does best in places with sandy or gravelly soils that drain well. It is also known to grow well next to roads, where it can get plenty of sunlight and water from nearby runoff.
What really interests me about this plant is that it can grow in places that have recently been disturbed and are now open to the sun. This plant can grow in a lot of different places. I’ve seen it in fields, meadows, and on the edges of forests.
There are so many natural resources around me that I feel thankful every time I see an evening primrose in the wild. It’s a reminder that nature gives us everything we need to live, but we have to love and take care of it.
Now let’s talk about how to tell evening primrose from other plants. This pretty flower is a great place to start foraging if you’re new because it’s pretty simple to tell apart once you know what to look for.
The evening primrose is a biennial herbaceous plant that can be told apart from other plants by its leaves, flowers, and seeds.
In its first year, the plant grows a basal rosette of lance-shaped leaves with wavy edges and a light-colored midvein that stands out. It does not flower in its first year.
As the plant grows into its second year, it forms a woody stalk with closely-spaced, shallowly toothed leaves that are arranged in pairs. This stalk grows straight up from the plant’s base and can get as tall as 5 feet. Flowers that are fragrant and pale to bright yellow have four petals that are about 1 to 2 inches wide. They bloom in the summer. The flower, which gives the plant its name, opens in the evening. Moths love the nectar they hold and eat it all up.
After the flowers have bloomed, they produce a long, narrow capsule that contains dozens of small seeds. The capsule is typically green when it first forms and then turns brown as it matures.
When you’re out foraging for evening primrose, keep an eye out for all of these characteristics. The leaves, stem, flowers, and fruit will all help you identify this wonderful plant. As always, only take what you need and leave plenty for wildlife and other people who are also foraging. Happy hunting!.
Primrose vs. Evening Primrose
I’ve had many people ask me what the difference is between garden primrose and evening primrose. The truth is. evening primrose is nothing like a garden primrose (Primula sp. ), which isn’t even in the same order, much less the same family. So, when it comes to identifying evening primrose, even beginner foragers will have no trouble telling them apart. Find out where to find evening primrose, how to tell it apart, and what to do with it by reading on.
How to harvest Common Evening Primrose (Oenothera biennis) seeds
FAQ
When to collect primrose seeds?
Are evening primrose seeds good for You?
Evening primrose seeds can be used to make an oil that is said to have a number of health benefits. The oil is said to be helpful for a variety of conditions, including dry skin, eczema, and psoriasis. It is also said to be helpful for reducing inflammation and pain, and for improving sleep.
How to harvest evening primrose?
You will need a pair of gloves, a pair of scissors, and a paper bag to collect the seeds. Follow these steps to harvest evening primrose plant: Wait until the flowers start to fade and turn brown. Put on your gloves and use your scissors to cut off the seed pods from the stem.
How do you grow evening primrose seeds?
1. Collect the seed pods from the plants. 2. Break open the seed pods and remove the seeds. 3. Spread the seeds out to dry in a warm, dry place. 4. Once the seeds are dry, store them in an airtight container in a cool, dark place. Harvesting your own evening primrose seeds is a great way to get fresh, healthy seeds for use in your own home.
Do evening primrose seeds fall out of flower heads?
The seeds will fall out of the flower heads as they dry. Once the seeds are dry, you can store them in a cool, dry place for future planting. Evening primrose seeds can be used to grow new plants, or they can be added to salads, smoothies, and other dishes.
What are the benefits of harvesting evening primrose plant?
Harvesting evening primrose plant can provide many benefits. Here are some of the benefits of harvesting evening primrose plant: Medicinal Properties: Evening primrose seeds are rich in gamma-linolenic acid (GLA), which has anti-inflammatory properties. This makes it an effective treatment for PMS symptoms, menopausal symptoms, and skin disorders.
How long do primrose seeds last?
The seeds can be stored in a cool, dry place for up to one year. They can be used to sow new plants or to make tea, oil, and other products. Evening primrose seeds can be stored for up to one year in a cool, dry place. The seeds should be kept in a sealed container to protect them from moisture and pests.