Why are my evening primrose not flowering

Why are my Evening Primrose not Flowering?

Today you learn why are my evening primrose not flowering in your garden.

Oenothera is a native flower of America. It is a genus of about 145 species of herbaceous flowering plants.

Commonly it is called Evening primrose, Evening star, and Sundrops.

They attract beautiful butterflies, bees, and particularly moths. 

Quick Guide

Common Nameevening primrose, evening star, sundrops
Scientific NameOenothera biennis
Life span2 years
Mature Size6 feet
Sun Exposurefull-sunlight and light shade
Soil TypeAverage and well-drained
Soil pH5.5 to 6.0
Bloom Timelate spring to late summer
Flower ColorYellow, white, purple, pink, or red
Hardiness Zones8 to 10
Native AreaEastern and central North America 

Evening Primrose Flowers

It is known for its beauty and has large, goblet-like flowers that grow with four petals and have yellow, white, or pink colors.

Its leaves form a circle in the base of the stem at ground level and spiral up to the flowering stems. Many species of flowers are open in the evening (may take a minute), hence named as “evening primrose“. 

Why are my evening primrose not flowering

Most species have yellow flowers, but few species have white, purple, pink, or red. Most native desert species are white.

A species of western North America called “Oenothera caespitosa”, produces white flowers that turn pink with age. One of the most typical features of the flower is the stigma, which has four branches in an X shape.

Once planted for its adorable roots, evening primrose (Oenothera) is now often grown for its omega-6-containing seeds.

Oenothera is also known as a coffee plant, the golden candlestick, and a host of other nicknames – can be biennial, annual, or perennial.

The plant reaches a height of 6 feet and a width of 24 inches.

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Naturally, evening primrose flowers are pollinated by insects like bees and moths.

Like many other species, their pollen grains are also loosely held by viscin threads. So, insects can effectively pollinate the flower.

Unfortunately, Evening primroses are a tasty treat for Lygus bugs and leafhoppers, as well as Japanese beetles.

Some gardeners plant them to trap Lygus bugs, leafhoppers, as well as Japanese beetles to protect more desirable plants like roses.

How to grow from seeds

Evening primroses are typically grown from seeds. You can buy their seeds from a nearby nursery or collect them directly from plants that grow roadside.

  • To collect seeds, cut one flower and dry it in sunlight for 2-3 days. 
  • After the flower gets dried its tiny seeds get visible, use these seeds to thrive more plants.
  • Plants in autumn or in early spring, planting in this duration often gives the best results.
  • Choose a spot that receives full sunlight. Do not plant in shade otherwise, they will not bloom.
  • Scrub the soil to make it smooth and spread some fertilizer. Good quality soil is essential for good growth. 
  • Make a hole with your finger, put 2-3 seeds into the hole, and cover it with soil.
  • Water the soil to make it moist. Keep watering regularly, after two weeks the seeds will germinate. 

In the first year of planting, they do not bloom, simply produce a leafy rosette at ground level.

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Can you transplant?

Evening primroses are not very invasive in nature, if you plant them in flower beds they will grow gently. If you transplant they might not get settled so it’s better to grow from seeds.

How To Care For Evening Primrose Plant

Your evening primrose not flowering because you’re not taking care of them.

Even the most novice can grow this herbaceous perennial.

If you give it plenty of light and well-draining soil, chances are your evening primroses will be happier.


Evening primrose plants are mostly adaptable and depend upon their variety. They grow well in full sunlight as well as light shade.

But, most of the varieties love sunlight. So, plant in a spot where they get at least six to eight hours of sunlight. They look lovely in grouping and spread like a groundcover.


Soil is another essential factor to grow successful evening primrose.  They need well-drained soil. Soil should be moist but not water-logged.

You can add a thick layer of mulch around the base to retain moisture that will keep roots cooler throughout the summer.


They do best with adequate regular watering especially in hot climates during summer. If your plant’s leaves are turning brown or discoloring it is a sign that you are overwatering them.

Overwatering can cause problems like root rot and fungal diseases. To avoid or cure the plant water only when the soil looks dry. 

Temperature and humidity

While its blooms like to grow in the summer. They prefer cooler temperatures rather than hotter ones. 

This is because planting in early spring when the climate is not much hot gives them adequate time to get established (to grow roots and leaves).

As the plant gets well-settled they produce bright and vibrant flowers. Too much heat, in the beginning, can cause the plant to be leggy and resemble a weed in appearance.


Keep pruning or cutting them. This will encourage new growth. You can prune to maintain the plant’s shape. Cutting and plucking old and dried parts like leaves and flowers is called deadheading. 

Deadheading is very important as these dried parts often keep sucking nutrients from the plant. Removing them will redirect energy to growing new flowers and leaves.


Generally, they do not need to be fed if you have planted them in good-quality soil. But, if you work in bad-quality soil then mix some fertilizer or organic matter in the base soil.


Traditionally, the native Americans used the plant for treating bruises and it’s the root for treating hemorrhoids.

Today, the plant is oil pressed to make a capsule which helps in conditions such as eczema, rheumatoid arthritis, premenstrual syndrome, and osteoporosis.

Oenothera oils contain gamma-linolenic acid (a type of omega-6 fatty acid) which helps to regulate blood pressure and to keep the immune system functioning well.


Common evening primrose (Oenothera biennis L) can grow about 6 feet tall and can produce leafy stalks in the first year. Then in the second year adorned by large lemon-yellow flowers. You can find seeds on Amazon.

Mexican evening primroses (O. Berlandieri), on the other hand, spread endlessly.

This variety only gets 8 inches in height. The plant will grow in infertile (unproductive) soil, with minimum water and full sun.

They are native to Missouri, Nebraska, Kansas, Oklahoma, Texas, and Mexico, 

Evening primrose ‘showy’ (O. speciosa) also blooms in the heat and doesn’t require much water. It displays pink, pale lavender, or white and pink flowers and grows 18 to 24 inches tall.

Pale evening primrose (O. pallida), is a low-growing biennial native to the western United States. You can buy seeds via Amazon.

Are Evening Primroses Toxic?

Though it has lots of ingestible uses for humans, they are mildly toxic to pets. If your pet like a cat or dog shows symptoms like vomiting, skin or eye irritation, or upset stomach they immediately take it to an animal doctor.

Common pests and diseases

Primrose’s foliage is often eaten up by varieties of beetles. If you notice cut leaves or spider web of the plant it might get attacked by traditional pests like aphids, spider mites, and mealybugs. 

These pests do make much damage to the plant. But, you can use a burst of water to remove them from the plant.

If you notice their flowers and foliage are covered with dusty white powder then the plant is suffering from fungal disease. To get rid of apply insecticidal soap or neem oil.

Did I Miss Anything?

Now I’d like to hear from you: which tip from today’s post are you going to try first?

Or maybe, I didn’t mention your favorite plant-growing tip. Either way, let me know by leaving a comment below right now.

P.S. I myself reply to every comment

Before going if you want to grow beautiful flowers in your garden? Then click on these articles also.