Vervain is a broad name applied to a group of plants within the Verbenaceae family that have been used for centuries. This widespread use has created confusion, particularly when distinguishing between the general term “Vervain” and the more specific “Blue Vervain.” Although both plants share the same family lineage and possess similar traditional reputations, they are distinct botanical entities with different origins, physical traits, and primary applications.
The Botanical Distinction
The confusion between Vervain and Blue Vervain stems from their shared placement within the Verbena genus. While they belong to the same genus, they are recognized as separate species, meaning they possess distinct genetic makeups. The plant generally referred to as Common Vervain or European Vervain is scientifically known as Verbena officinalis. This species has a long history of use and is the one most often referenced in ancient texts and European herbalism.
Blue Vervain, on the other hand, is identified by the name Verbena hastata. This North American native species developed its own distinct characteristics and traditional uses. As distinct species, they may contain similar classes of compounds, but the ratios and specific chemical structures of compounds like iridoids and phenylpropanoid glycosides will vary. This slight difference in chemical composition is the underlying reason for the subtle, yet notable, differences in their effects when used in traditional practices.
Contrasting Physical Characteristics and Habitats
Verbena hastata, or Blue Vervain, is a tall, upright perennial that can reach heights of four to six feet. Its flowers are a distinct blue or purplish-blue color and are arranged in long, slender, candelabra-like spikes that bloom in mid-to-late summer. This species is indigenous to North America and thrives in moist environments, frequently being found in wet meadows, marshes, and along stream banks.
In contrast, Common Vervain (Verbena officinalis) exhibits a shorter, more sprawling growth habit, typically reaching a height of only about 28 inches. Its flowers are much paler, usually described as mauve, lilac, or pale pink, and are clustered in delicate, sparse spikes. V. officinalis is native to Europe and Eurasia but has become widely naturalized across the globe, often preferring drier, disturbed ground, roadsides, and limey soils.
Differentiating Traditional Applications
While both species are valued as nervines—herbs that support the nervous system—their specific traditional applications differ. Common Vervain (V. officinalis) has a long history of use dating back to antiquity. Historically, it was employed as a mild sedative and restorative tonic, often used to help with nervous exhaustion, anxiety, and disturbed sleep. Its use extended to promoting digestion and supporting liver and gallbladder function.
Blue Vervain (V. hastata) is recognized as a bitter tonic and antispasmodic. It has been traditionally used to address nervousness, stress, and anxiety, but with a specific focus on physical manifestations of tension, such as tight muscles in the neck and shoulders. The bitter taste of V. hastata stimulates digestive secretions, contributing to its historical use for stress-related digestive issues and appetite loss. V. hastata was also historically used to induce sweating to break fevers and was sometimes used as an emetic to induce vomiting.