American Blue Vervain

    Blue vervain is an attractive purple-blue perennial wildflower found across North America including most of the U.S. and southern Canada. The plant is erect and slender with small flowers appearing during the summer months.

    Scientific Name: Verbena hastata (L.)
    Common Name: Blue vervain, American blue vervain, swamp vervain, swamp verbena, blue verbena, Simpler’s joy, American vervain
    Plant Family: Verbenaceae (Verbena family)

    Etymology: Verbena hastata comes from the Latin word verbena meaning “sacred” or “bough.” In classical Latin, verbēna refers to leafy branches or twigs used in religious ceremonies or for medicinal purposes. Hastata comes from the Latin word hastatus which means spear-shaped or “armed with spears” typically referring to a leaf that is triangular with the corners laterally protruding.

    Traditional Uses

    Native Americans across North America utilized Blue Vervain for medicine and consumption. The leaves and roots were harvested year-round for medicinal purposes. The leaves of the Blue Vervain were first dried, then boiled to create a tea used as a spring tonic to strengthen organs such as the liver, kidneys, intestines, and lungs as well as soothing the nervous system. The roots were typically used for a wide range of illnesses and conditions due to their potency such as depression, fevers, colds, epilepsy, insomnia, headaches, and stomachaches among others. The Blue Vervain plant was also used as an antidote for American Pokeweed poisoning. For consumption, the seeds of the Blue Vervain were dried and ground into flour (typically bitter tasting). The flowers were also dried and powdered to combat nosebleeds by sniffing the substance. Native Americans often used the plant externally for wounds and sores as well.

    Edible Parts

    The seeds of the Blue Vervain are the primary edible portions of the plant. The seeds are typically dried or roasted and ground into a flour substitute. Due to the bitter taste, the seeds are often soaked in cold water to make the taste more pleasant. The leaves of Blue Vervain can be dried and boiled with hot water to make tea with medicinal properties. Roots can also be processed and consumed for medical purposes such as a tonic, for calming the nervous system, relieving pain, and treating mental illnesses. The vervain flowers can also be eaten in salads or used as a garnish. Consumption of Blue Vervain can interfere with blood pressure medications and hormone therapy. In large quantities it can also cause vomiting and diarrhea.

    Gathering and Using

    Blue Vervain plants can be gathered from the base if the whole plant is to be used or the portions of the plant’s leaves and flowers can be cut off. It is important to note this plant is important to pollinators and other wildlife, so collection of the plant should be minimal. Also, taking off only portions of the plant can leave it prone to diseases. It is preferable to collect the plant before and during the prime of its flowering during the summer months (June-September). The leaves of the plant can be dried and brewed into teas. Blue Vervain typically has a bitter taste but leaves and seeds can be soaked in cold water multiple times to offset the bitterness. The roots of the plant can be used for internal medicine to treat depression, anxiety, coughs, colds, fevers, stomachaches, cramps, jaundice, and headaches. Externally, the roots can be used to heal wounds, sores, ulcers, and acne. Although there are no valid clinical trials, vervain is considered a purported galactagogue which can potentially increase production of breast milk with infusion of the root.

    Permaculture Functions and Considerations 

    External and internal medicinal usages, borders, meadows, food source for wildlife, larval host, pollinators, good pioneer species, and streambank stabilization. Blue Vervain is often used for landscaping as well due to its beautiful purple flowers and ability to grow on degraded land.

    Habitat

    Blue Vervain can be expected to grow in areas with moist to wet soil and full to partial sun. It is often found in meadows, streambanks, pastures, marshes, waste areas, fields, river bottom prairies, and ditches. It can grow in degraded lands and disturbed areas. The Blue Vervain plant has a moderate to high tolerance of salt, nutrient load, and siltation.

    How to Identify

    Blue Vervain is an erect perennial wildflower that can grow from 2-6 feet in height, with a spread of 1-2.5 feet. It has square stems that can be green or red and are covered with small, white hairs. The green leaves are toothed, opposite, and spear shaped, with a length of about 6 inches and a width of about 1 inch. The flowers, which bloom from June-September, are arranged around the spikes protruding from the stem and have a purple-blue coloration. The flowers are also 5-lobed, tubular, and tightly packed on the vervain spikes. The spikes of the plant are about 5 inches in length and are “pencil-shaped.” The flowers do not have a strong scent. Following the blooming period, the flowers are replaced by four nutlets each that are up to 2mm long and have a red-brown coloration.

    Blue Vervain

    Reveal, James L. 2008

    Blue Vervain

    Cardina, John. Accessed February 2022

    Blue Vervain

    Vick, Albert F.W. 1990

    Wildlife Support

    Blue Vervain serves as an essential wildlife support component for consumption and pollination. The seeds are consumed by many birds including the cardinal, field sparrow, swamp sparrow, song sparrow, and slate-colored junco. Long- and short-tongued bees are attracted to the plant primarily for its nectar but occasionally its pollen as well. Although most mammals (aside from the cottontail rabbit) typically do not feed on the leaves due to its bitterness, the caterpillars of the verbena moth consume the leaves. The plant also serves as a larval host for the Common Buckeye butterfly among other larvae of moths and butterflies.

    Additional Information

    The “old-world” species of vervain called Verbena officinalis (native to Europe) also served as a sacred plant throughout history. Early Roman priests believed the flowers were formed from the goddess Juno’s tears. The flowers were also used to decorate altars and sacrificial animals. This form of vervain was said to be utilized in witchcraft to ward off plagues, evil spirits, and storms in medieval times. Although there is little evidence, Verbena hastata was believed to be used to ward off vampires in folklore but it was primarily believed to be used to ward off diseases.

    Sources

    • Drugs and Lactation Database (LactMed) [Internet]. Bethesda (MD): National Library of Medicine (US); 2006–. Vervain. 2021 Feb 15. PMID: 30000912.
    • Kirk, Samantha. Belt, Shawn. USDA NRCS Plant Materials Program. USDA NRCS. “Plant Fact Sheet for Blue Vervain (Verbena hastata).” Norman A. Berg National Plant Materials Center. February 2011.
    • Mitchell, Gordon. Indiana Native Plants. “Blue Vervain.” Accessed February 25, 2022.
    • NC State Extension. “Verbena Hastata.” North Carolina Extension Gardener Plant Toolbox. Plants.ces.ncsu.edu. Accessed February 25, 2022.
    • OED Online. Oxford University Press, “verbena, n.” December 2021. Accessed February 26, 2022.
    • Stebbins, Hayden. The Eclectic School of Herbal Medicine. “Blue Vervain.” 2015. Accessed February 27, 2022.
    • TWC Staff. Lady Bird Johnson Wildflower Center. University of Texas Austin. “Verbena hastata” org, December 2019.
    • Vogel, Joanne. Duke Farms. “Bee Friendly Flowers Week 9: Vervain.” September 2020.
    • Northeast School of Botanical Medicine. “Blue Vervain (Verbena hastata) Monograph-Medicinal Uses, Preparations, and Botanical Notes.” November 29, 2019.

    Web Sources


    Planting Considerations

    • USDA Hardiness Zone: 3 to 8
    • Native Range: North America (U.S. and southern Canada)
    • Forest Garden Layer: Herb
    • Height: 2.00 to 6.00 ft
    • Spread: 1.00 to 2.50 ft
    • Growth Rate: Medium
    • Sun: Full to partial sun
    • Bloom: June to September
    • Attracts: Birds, butterflies, moths, bees
    • Tolerates: Wet soil, disturbed lands, moderate to high salt, nutrient load, and siltation
    • Drawbacks: No known pests or disease, consumption can interfere with some medications
    • Soil moisture: Moist, wet
    • Soil texture: Clay, loam (silt), sand
    • Soil pH: 6-7 preferred, mildly acidic, neutral, mildly alkaline

    Plant profile by Sophie Esdale '24