Blue Vervain is a perennial wildflower native to North America. Scientifically known as Verbena hastata, it grows 2-5′ tall in full sun and moist soil. Blooming purple spikes of flowers for 6 weeks in Summer, it attracts numerous pollinators as well as birds who eat the seed. Finally, it has a rich history being used medicinally by Native Americans.
In this article:
- What is Blue Vervain
- What are the benefits of Blue Vervain
- Identification / Characteristics
- How to grow and care for Blue Vervain
- What Wildlife, Pests, and Diseases effect Blue Vervain
- Where to buy Blue Vervain
- Uses of Blue Vervain
- Final thoughts
What is Blue Vervain
One of the most overlooked yet beautiful perennial wildflowers native to North America, Blue Vervain grows most often near water in moist to wet soil, and can tolerate brief periods of flooding. Often found in ditches and near wetlands, it provides long periods of purple flowers arrayed on spikes, giving almost a ‘torch-like’ appearance but purple. [1][2][3]
The flowers primarily produce nectar which attracts dozens of species of bees, butterflies, and moths. [4] It also hosts larvae from several insects, adding to it’s wildlife value. Finally, birds are known to eat the seeds in Autumn and Winter, as I’ve witnessed this on my own plants.[3] Yet the mature foliage is bitter and avoided by deer and rabbits. [2]
Used by many native Americans for thousands of years, the leaves and roots were used to treat a variety of symptoms. And it continues to be used today, and Blue Vervain supplements can be purchased. Although it has been documented that Blue Vervain can induce vomiting and diarrhea in large doses, and can also interfere with other medications. So – don’t consume this plant unless you’ve consulted with your doctor. [2]
**Note – if you LOVE this style of flower but have dry conditions, consider trying it’s cousin, Hoary Vervain. It’s much more drought tolerant.
Blue Vervain Facts
- Nearly 70 different species of pollinators have been documented visiting Blue Vervain, proving it’s high value to wildlife.
- One of the most widespread plants native to North America, it is present in 48 of 50 states, and most provinces of Canada
- A member of the Verbenaceae family, Blue Vervain (Verbena hastata) shares a similar resemblance to it’s European cousin Verbena officinalis
- Blue Vervain was extensively used by Native Americans medicinally to treat a wide variety of ailments
- Herbalists today still use Blue Vervain, although one should consult with their medical provider before taking any supplements or tea
- The bitter taste of the foliage dissuade deer and rabbits from eating mature leaves.
Native Range of Blue Vervain
Blue Vervain is native to all of the 48 continental United States and seven of the lower Canadian Provinces (all but Alberta). However, while native to all 48 states, it’s primary native range is in the Midwest and Northeast United States, and Southern Manitoba, Ontario, and Quebec.
Blue Vervain Reference Table
| Scientific Name | Verbena Hastata |
| Common Name(s) | Blue Vervain, American Blue Vervain, Blue Verbena, Swamp Verbena, Simpler’s Joy, Wild Hyssop |
| Native Range, USDA Zone | North America, USDA Hardiness zones 3-8 |
| Bloom Time | July-September |
| Bloom Duration, Color | Six-weeks, pink to purple |
| Height | 2-6′ (60-180 cm) |
| Spacing / Spread | 1-2′ (30-60 cm) |
| Light Requirements | Full sun to partial shade |
| Soil Types | Sandy loam to clay loam |
| Moisture | Wet to medium |
| Fauna Associations / Larval Hosts | Numerous bees/butterflies / Common Buckeye, Verbena Leaf Midge, Verbena Moth |
What are the Benefits of Blue Vervain
Wildlife
Blue Vervain attracts a wide variety and quantity of pollinator species, which directly benefits many pollinators. Everything from large bumblebees, honey bees, butterflies, and hummingbird moths will visit Blue Vervain for nectar. Furthermore, numerous species of songbird eat the tiny seeds in Winter.
Beauty
The clusters of purple flower spikes are gorgeous and really can add an accent to a flower bed or garden. Mass plantings will create a more dramatic effect, allowing it to stand out more. But when examined up close, the individual blooms are so intricate they provide a beauty themselves.
Great cut flower
If you like to take cut flowers from your garden to make bouquets, Blue Vervain is a great addition. The spikes of purple flowers make great accents and tend to look great with any yellow, pink, or purple flower. Personally I think it goes with anything. But, the cut flowers will likely outlast most other species in the vase.
Long Bloom Time
Blooming for six weeks in mid to late Summer, Blue Vervain adds a long dose of color to a garden. And this helps it bridge any blooming gaps in more traditional perennials, thus providing more food for local pollinators as well as color.
Can fight invasive plants
Growing in similar conditions as the invasive Purple Loosestrife, Blue Vervain can make for an excellent replacement once the aforementioned invader has been eradicated.
Identification and Characteristics of Blue Vervain
Blue Vervain typically grows 2-5′ tall depending on access to moisture and sunlight. It generally withstands all winds and is erect, which is a benefit for a taller perennial.
Stalk
The stalk of Blue Vervain is green to reddish green in color and has a four-angled shape. The upper portion will sometimes have branching.
Leaf
Leaves of Blue Vervain are opposite (paired) along the stem and 1″ wide (2.5 cm) up to 6″ long (15cm). They are lanceolate in shape and coarsely serrated, and will have prominent veins. They vary from a reddish-purple to green in color.
Flower
Panicles of flower spikes containing lavender to purple/violet flowers up to 5″ long occur where the stem terminates. The individual flowers are small, typically 1/4″ diameter and long (6 mm). There will be 5 petals (lobes).[3]
The blooming period lasts approximately six weeks starting in early to mid-Summer. Spikes bloom from bottom to top, and and individual flower blooms for 5-7 days. Blooming initiates based on conditions, so if a plant is in more shade, it may start blooming a bit later, thus prolonging the overall blooming period for a location.
Approximately 4-6 weeks after blooming, the flowers are replaced by small nutlets. They are approximately 2 mm long by 1/2 mm wide and cylindrical in shape, brown to red in color.
Root
The root system is fibrous and has short rhizomes.
Grow and Care for Blue Vervain
Sunlight Requirements
Blue Vervain will grow best in full sun, which is at least six hours of direct sunlight per day. It can tolerate partial sun, which is 4-6 hours of sun per day, but will not be as tall and showy.
Soil Requirements
For soil, Blue Vervain is not too picky, as it can grow in anything from sandy loam to clay as long as it doesn’t dry out too much.
Moisture Requirements
Blue Vervain will grow best in wet to moist soil, and that is where you most often encounter it in the wild. It can grow in well-draining soil with medium moisture as well. I often find it growing near water such as creeks or ponds. It can grow in drier well-drained areas though, as long as it receives some afternoon shade.
Maintenance
For maintenance, Blue Vervain can easily self seed in formal flowerbeds without competition. So you should either deadhead them, or just pull any unwanted seedlings.
But this flower generally stands tall in the face of strong winds, and shouldn’t require staking or The Chelsea Chop.
Do you need to cut back Blue Vervain (Verbena) for winter?
Blue Vervain (Verbena hastata) will self-seed prolifically during the fall and Winter months, leading to dozens of new seedlings in the Spring. If you do not want all these plants to sprout up, such as in a formal mulched flower bed, then you should deadhead the spent flower stalks in late Summer or early Fall, taking care to minimize the number of seeds that drop.
However, there is benefit to leaving the stalks up. There are songbirds who enjoy the seed, and leaving the seed heads up is one of the main reasons to not cut back Blue Vervain (Verbena) stalks in Fall,.
Fertilizer
Blue Vervain should not require supplemental fertilizer. However, if you desire very tall plants but are planting it in infertile soil without much organic matter (like a former lawn), then it would be helpful to add a handful of compost when planting.
Saving seed from Blue Vervain
To save seed from Blue Vervain, wait for the seed heads to turn brown and begin to dry on the plant (usually early September for zone 6). Then, carefully hold the stalk below the seed head and cut the stalk below your hand, using pruning shears or sturdy scissors. Note that a single cluster of seed heads will probably contain well over 1000 seeds.
Without turning the seed heads upside down, move the seed head spike cluster into a paper bag or container. Take them to a cool dry place, out of direct sunlight for another week or two so that the seed heads can fully dry.
Then, over a paper plate, pick up the seed heads from the bag, and just tap them on the plate. The seed will easily fall off. After you are done with the seed heads, tip the bag upside down over the plate to collect any remaining seed.
How to Grow Blue Vervain from Seed
Blue Vervain seed requires a 30-90 day cold stratification period and exposure to sunlight to break dormancy. In nature, the seeds naturally fall from the seedheads near the mother plant, and rest on the soil surface all winter until Spring. [2][5]
So, to successfully grow and germinate Blue Vervain from seed, you need to cold stratify it for 30 days, or Winter Sow the seed, and only press the seed into the soil surface.
Process to plant Blue Vervain Seed
The following steps assume you have either cold stratified the seed in the refrigerators, or are Winter Sowing the seed.
- Fill a suitable container with moist potting soil
- Sprinkle 5-10 Blue Vervain seeds on the soil surface
- Press the seeds in with your thumb, but don’t cover or bury them
- Place the container in a location that receives morning sun and afternoon shade
- Seeds should germinate within two weeks, or once Spring arrives if Winter Sowing
Often you will have many seeds germinate. When this occurs, you should determine how many plants you want, and then either thin the seedlings or divide and separate the seedlings, potting them up to larger size containers. This will allow your young plants to grow to a larger size before transplanting out to their final location.
Establishment of Blue Vervain
If transplanted to it’s final location early enough, it will bloom the first year. In fact, if a seedling is just potted up into a large enough container (6″ square) or more, it will often bloom inside the pot by late Summer (personal experience).
Direct sowing Blue Vervain seed
Blue Vervain seed can be direct sowed. To do so, rough up the area you wish to plant them. Then in Autumn until very early Spring (as in late Feb or March) scatter seeds over this area. Next, walk over the area to ensure good contact with the soil. Note that it is better to direct sow in late Winter or early Spring, as birds do eat the seeds.
Propagation by cuttings
Blue Vervain can be propagated by cuttings. Taking 3-4″ long stem tip in early Spring, removing lower leaves and insert into sand/perlite rooting mixture. Sufficient roots should develop in 4-6 weeks. [2]
Wildlife, Pests, and Diseases associated with Blue Vervain
Pollinators
Blue Vervain can attract a huge variety of pollinators, as Charles Robertson in his 1929 survey recorded nearly 70 unique species. [4] Some examples include long and short-tongued bees, as well sweat bees and wasps. Butterflies and moths are also attracted to the flowers for nectar, as well as hummingbirds and hummingbird moths. [2]
Pests
Some insects will feed destructively on the foliage. This is normal and part of the natural ecosystem, and the plant will not be harmed. But certain larvae of beetles, aphids, and the appropriately named Verbena Moth & Verbena Leaf Midge will all consume the foliage. [3]
Please note that this will not result in defoliation of the plant, but will affect the appearance.
Birds
Several different songbirds are known to eat the seeds of Blue Vervain. The Cardinal, Dark-eyed Junco, and various sparrows have been documented consuming seed. [2][3]
Deer and Rabbits
Blue Vervain is vulnerable to deer and rabbits when young, or early in Spring when emerging. New or young growth may be browsed upon. If you are subject to strong rabbit of deer pressure, I strongly recommend you protect them with Liquid Fence until they are a couple feet tall.
Disease
Generally disease free, it can get a white mold or fungus on the leaves. The effects are cosmetic and it will not be fatal to the plant. But, thin out the area to increase airflow to reduce the occurrence.
Where you can buy Blue Vervain
Blue Vervain is not typically sold in big-box stores of large nurseries. But it can be purchased at specialty nurseries that deal in Native Plants. You can find native plant nurseries near you on our interactive map.
Where to buy seeds
We have ordered a variety of native flower seeds from Everwilde Farms, which you can order right from Amazon through our link on our RECOMMENDED PRODUCTS PAGE. (We may earn a small commission when you purchase through our links, at no cost to you. This helps support our website.)
Uses of Blue Vervain
Garden Uses
Blue Vervain is very versatile in that it can be used in a formal, mulched flower bed (if deadheaded to avoid self-seeding), native plant garden, wildflower meadow, border garden, or micro-prairie. Ideally you should place it in the back (North) of a flowerbed due to it’s tall height so it doesn’t shade out other smaller flowers.
If you wish to have smaller, bushier plants, then you can cut back the plant several times throughout the growing season (see Chelsea Chop).
Companion Plants
As you commonly find it growing in wet areas, Blue Vervain would grow well with other moisture loving flowers such as:
- Blue Lobelia
- Boneset
- Cardinal Flower
- False Sunflower
- Halbred-Leaf Rose Mallow
- Ironweed
- Jewel Weed
- Joe Pye Weed
- Liatris Spicata
- Swamp Milkweed
Native American uses
*NOTE* – Blue Vervain has been documented to induce vomiting and diarrhea in larger doses. It can also interfere with certain blood medications or hormone therapies. Consult your doctor before consuming any Blue Vervain. [2]
There are 29 uses of Blue Vervain documented for nine different Native American tribes.[6][7] Leaves and roots were harvested for medicinal purposes. Some uses include:
- Antidepressant
- Antidiarrheal
- Fevers
- Taken as a cough/cold medicine
- Cramps
- Liver/kidney disease
- To treat acne, ulcers, and cuts.
- Roots used to ‘clear up cloudy urine’
Medicinal Uses
*NOTE* – Blue Vervain has been documented to induce vomiting and diarrhea in larger doses. It can also interfere with certain blood medications or hormone therapies. Consult your doctor before consuming any Blue Vervain. [2]
Traditionally Blue Vervain has been used by herbalists to treat a variety of ailments. It even received a lengthy article detailing it’s uses in early American Clinical Journals amongst other historical medical publications.[8] In fact Blue Vervain supplements can be purchased today. Most of these documented uses mirror the Native American uses such as an cough/cold treatment, fever reducer, antidiarrheal, emetic, sedative…etc.
But there has been, and is currently research on-going as to the medicinal properties of Blue Vervain. In particular as to how they could potentially be turned into medicine. Research into the antidiarrheal properties, and how Blue Vervain leaf extract can reduce AGEs to treat later stage aging and diabetes is on-going.[9][10] Additionally research has borne out that leaf extracts have anti-inflammatory properties that can aid in treating respiratory or bronchial sickness. [11]
Final Thoughts
Blue Vervain is a tall beautiful flower that provides a long bloom time and help bridges any color gaps in the garden. Furthermore, it supports a large array of pollinators, which directly impacts your local ecosystem in a very positive way. Even if you don’t want a ‘wild’ garden, with deadheading you can reduce the chances of any self-seeding, which effectively turns it into a ‘residential friendly’ native plant.
It would be nice if this flower were cultivated more, as it is a showy flower that greatly benefits the local ecosystem. Plus the fact that it is native in 48/50 states, and most provinces of Canada mean you can grow it without risk of introducing a non-native species.
Find more native plants here
References:
[1] – Verbena Hastata. USDA NRCS. Accessed 10JAN2023
[2] – Kirk, S. and S.Belt. 2010. Plant fact sheet for blue vervain (Verbena hastata). USDA-Natural Resources Conservation Service, Norman A. Berg National Plant Materials Center. Beltsville, MD 20705. Accessed 10JAN2023. Archived from original 10JAN2023.
[3] – Holm, Heather. Pollinators of native plants : attract, observe and identify pollinators and beneficial insects with native plants, Minnetonka, MN : Pollination Press LLC, 2014, pp301.
[4] – Robertson, Charles. “Flowers and insects; lists of visitors of four hundred and fifty-three flowers.” (1928).
[5] – Shipley, B., and Mo Parent. “Germination responses of 64 wetland species in relation to seed size, minimum time to reproduction and seedling relative growth rate.” Functional ecology (1991): 111-118. Accessed 10JAN2023
[6] – Moerman, Daniel E. Native American medicinal plants : an ethnobotanical dictionary, Portland, Or. : Timber Press, 2009, pp 799.
[7] – ‘Verbena Hastata‘. North American Ethnobotany Database. Accessed 10JAN2023.
[8] – French, J.M. ‘Therapeutic Properties of Verbena Hastata’. The American Journal of Clinical Medicine 1910-11: Vol 17 Iss 11, Medical Digest Inc, 1911, pp1173-1177.
[9] – Akuodor, G. C., et al. “Ethanolic leaf extract of Verbena hastata produces antidiarrhoeal and gastrointestinal motility slowing effects in albino rats.” Journal of Medicinal Plants Research 4.16 (2010): 1624-1627.
[10] – Yokosuka, Akihito, et al. “Chemical Constituents of the Whole Plant of Verbena hastata and Their Inhibitory Activity Against the Production of AGEs.” Natural Product Communications 16.4 (2021): 1934578X211009727.
[11] – Edewor, T. I., and L. A. Usman. “Cytotoxicity and antibacterial activity of the leaf methanolic extract of Verbena hastate.” Journal of Medicinal Plants Research 6.1 (2012): 55-58. Accessed 10JAN2023.
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