What is the difference between mullein and evening primrose?

January 4, 2026 •

3 min read

While often confused due to visual similarities, mullein ($Verbascum~thapsus$) and evening primrose ($Oenothera~biennis$) are distinct plants with different primary applications in herbal medicine. A primary physical differentiator is mullein's soft, woolly leaves compared to evening primrose's smooth, non-fuzzy ones.

Quick Summary

Mullein and evening primrose are two different biennial plants with distinct physical characteristics and medicinal uses. Mullein is mainly for respiratory health, while evening primrose oil is valued for women's hormonal and skin health.

Key Points

Leaf Texture: Mullein has soft, woolly leaves, while evening primrose has smooth, non-fuzzy leaves.
Flower Petals: Mullein flowers feature five petals, whereas evening primrose flowers have only four.
Bloom Time: Mullein flowers open during the day, but evening primrose flowers open in the evening.
Primary Use: Mullein is used for respiratory issues, while evening primrose oil targets women's health and inflammatory conditions.
Toxic Seeds: Mullein seeds contain a toxic compound, while the evening primrose plant is generally edible when properly prepared.
Key Compounds: Mullein contains soothing mucilage, while evening primrose oil is rich in GLA and LA fatty acids.

The Key Distinctions: Appearance, Uses, and Compounds

For foragers, gardeners, and natural health enthusiasts, correctly identifying mullein and evening primrose is crucial for safety and efficacy. Though both are biennials that form a basal rosette in their first year and send up a flowering stalk in their second, their differences are numerous and significant.

Botanical and Physical Differences

Leaves: The most obvious differentiator is the leaves. Mullein (often called woolly mullein) has large, fuzzy, and grayish-green leaves with a velvety texture, covered in dense silvery hairs. Evening primrose, conversely, has smooth, non-fuzzy, lance-shaped leaves that are a darker green.
Flowers: A close inspection of the flowers reveals more differences. Mullein flowers have five petals and are densely arranged in a compact formation around the flower stalk. They also typically open during the day. Evening primrose flowers have four petals, are more spaced out along the stalk, and famously open in the evening, often unfurling in front of your eyes as the sun sets.
Seed Pods: The seed pods are also distinct. Mullein produces small, ovoid capsules, while evening primrose forms longer, downy pods.

Different Medicinal Applications

The most significant differences lie in their medicinal applications. Each plant offers a unique set of benefits based on its chemical composition.

Mullein's Respiratory Support

Mullein is best known for its potent respiratory benefits. Its leaves and flowers contain mucilage, a gummy substance that soothes irritated mucous membranes, making it a powerful expectorant. This helps the body to expel mucus and is used to treat conditions like:

Asthma
Bronchitis
Coughs
Colds
Sore throats

Additionally, mullein flower-infused oil is used topically to treat earaches and infections, though one must ensure the eardrum is not perforated before use. The flowers contain other compounds, including saponins, which further contribute to its expectorant properties.

Evening Primrose's Hormonal and Skin Health Benefits

Evening primrose, particularly its oil extracted from the seeds, is prized for its high content of omega-6 fatty acids, specifically gamma-linolenic acid (GLA) and linoleic acid (LA). These fatty acids play a crucial role in hormonal regulation and anti-inflammatory processes. The primary uses for evening primrose oil (EPO) include:

Alleviating symptoms of premenstrual syndrome (PMS)
Managing symptoms of menopause, such as hot flashes
Improving skin conditions like eczema, acne, and overall hydration due to its anti-inflammatory effects
Reducing inflammation associated with conditions like rheumatoid arthritis

Comparison of Mullein and Evening Primrose


Feature	Mullein ($Verbascum~thapsus$)	Evening Primrose ($Oenothera~biennis$)
Leaves	Large, silvery, fuzzy, woolly texture	Smooth, non-fuzzy, lance-shaped
Flowers	5 petals, densely packed, open during the day	4 petals, spaced out, open in the evening
Primary Medicinal Use	Respiratory ailments, earaches	Women's hormonal health, skin issues, inflammation
Key Compounds	Mucilage, saponins, flavonoids	Gamma-linolenic acid (GLA), Linoleic acid (LA)
Edibility	Warning: Seeds contain rotenone and are toxic. Leaves and flowers must be strained to remove irritant hairs for tea.	Whole plant edible (root, leaves, flowers, seeds) when prepared correctly.

Safety and Preparation Considerations

Both plants require careful handling and preparation. Mullein leaves must be finely strained before making tea to remove the irritating hairs that can cause a tickle in the throat. More importantly, mullein seeds contain rotenone and should not be ingested. Evening primrose, while generally edible, can cause digestive upset if consumed in large quantities. As with any herbal supplement, consulting a healthcare provider before using either plant medicinally is recommended, especially for pregnant or nursing women. A good resource for understanding mullein's respiratory benefits is the Cleveland Clinic Health Essentials, which discusses how it helps clear mucus and calm inflammation.

Conclusion

While both mullein and evening primrose may be seen in the same natural habitats and share a biennial life cycle, their unique characteristics set them far apart. Mullein's signature fuzzy leaves and respiratory applications stand in stark contrast to evening primrose's smooth leaves and benefits for hormonal and skin health derived from its oil. Understanding these key differences is essential for anyone seeking to responsibly incorporate these two distinct and potent herbs into their wellness routine.

Frequently Asked Questions

No, mullein and evening primrose have different medicinal properties and active compounds, so they cannot be used interchangeably.

Look at the leaves. Mullein has distinctive fuzzy, silvery leaves, while evening primrose has smooth, green leaves. Checking the flower petal count (five for mullein, four for primrose) and bloom time is also a reliable method.

Mullein is not toxic in the same way. The leaves and flowers are generally safe when prepared correctly (strained for tea), but the seeds are toxic and should not be ingested due to the rotenone they contain. Evening primrose is considered safe and its parts are edible.

Evening primrose oil, extracted from the seeds, is used to manage symptoms of PMS, menopause, and skin conditions like eczema, thanks to its high omega-6 fatty acid content.

Mullein's primary benefit is for respiratory health. Its mucilage acts as a soothing expectorant to help clear mucus from the lungs and calm throat irritation.

Evening primrose is considered better for skin issues. Its oil contains anti-inflammatory fatty acids that can help with conditions like acne, eczema, and general skin hydration.

No. All parts of the evening primrose plant can be edible (roots, leaves, flowers), while only the leaves and flowers of mullein are used, and they must be strained to remove irritating hairs. The seeds of mullein are toxic.