Pycnanthemum virginianum (Virginia Mountain Mint)


If attracting pollinators to your yard is one of your gardening goals, then you should really consider adding Virginia Mountain Mint to your garden. The small white flowers are irresistible to pollinating insects. The tiny flowers bloom for a month or more in Summer, and are amazing with how well they attract pollinators.

In this article:

What is Pycnanthemum virginianum

Pycnanthemum virginianum is a herbaceous perennial native to Eastern North America. Commonly known as Virginia Mountain Mint, it will grow 2-3′ tall in full sun and well draining soil and bloom numerous white flower heads for a month or more. One of the best plants at attracting pollinators, numerous species of insect visit the flowers. [1] [2]

The foliage gives off a minty aroma when crushed, just like other mountain mints. This helps keep the leaves looking great throughout the growing season as deer, rabbits, and leaf-feeding insects avoid Pycnanthemum virginianum.

Native Range of Pycnanthemum virginianum

The native range of Pycnanthemum virginianum (Virginia Mountain Mint) is the Midwestern and Eastern United States, Canada, and small pockets in Mississippi, Oklahoma, Arkansas, Tennessee, Alabama, Georgia and North Carolina.

Sources [3] [4] [5] [6]

Reference Table

Scientific NamePycnanthemum virginianum
Common Name(s)Virginia Mountain Mint, Common Mountain Mint, Mountain Mint, Mountain Thyme, Prairie Hyssop, Pennyroyal
Native Range, USDA ZoneUSDA Hardiness Zone 2-3
Bloom TimeMid to late Summer
Bloom Duration, Color4-6 weeks, White
Height2-3′ (60-90cm)
Spacing / Spread12-18″ (30-45 cm)
Light RequirementsFull Sun, Partial Sun
Soil TypesSandy loam to Clay loam, rocky.
MoistureMoist to average-moist soil
Fauna Associations / Larval HostsNumerous bees, beetles, butterflies, flies.
Sources [1] [2] [3]

What are the Benefits of Pycnanthemum virginianum

Pycnanthemum virginianum (Virginia Mountain Mint) is good for attracting ridiculous amounts of pollinators to your garden, having a long bloom period, growing attractive foliage, and for the delicious minty aroma it’s foliage produces!

Pollinator madness!

If you thought you were familiar with the insects in your ‘neighborhood’, think again! Virginia Mountain Mint is going to bring in pollinating insects you’ve never seen before! I’m not kidding. I thought I was an observant gardener, but after 2 minutes looking at my mountain mint I realized there are a whole lot of species I wasn’t familiar with. What is also really cool is that you almost never see these pollinators on other flowers. It’s like there is a whole world of specialist pollinating insects that get no attention!

Beautiful foliage and shape

The leaves and branching of Virginia Mountain Mint make the overall plant seem like a small bush throughout the growing season. So, it will be attractive and interesting even when not in bloom.

Identification and Characteristics

Lifecycle of Pycnanthemum virginianum

In Spring,Pycnanthemum virginianum emerges with green foliage that is often purple on the underside of the leaves. You can always confirm it is a mountain mint by crushing some of the leaves. In Fall and Winter, the seed heads of Pycnanthemum virginianum will persist.

Stalk

Pycnanthemum virginianum typically grows 2-3′ tall (60-90 cm). The green or red stalk will be square in shape, or at least have four sharp angles, have small white hairs, and branch frequently, giving it a shrub or bush-like appearance.

Stalk / stem of Pycnanthemum virginianum

Leaf

Opposite linear leaves that are ~2″ long (5 cm) by 1/4″ (6 mm) wide are green in color and will have no petiole or stem. The edges are smooth, and if you crush them they release a strong minty aroma.

Leaf of Pycnanthemum virginianum

The foliage of Virginia Mountain Mint is generally attractive during the entire growing season. This is mainly because leaf-eating insects avoid the plant as well as deer/rabbits.

Flower

There will be many flower heads that are roughly 3/4″ diameter (9 mm) and flat containing many small flowers (25-50). The individual flowers are white in color and often have purple dots.

The flowers do not bloom all at once, but only a few at a time, working their way from the outside edge to the center.

The blooming period for Pycnanthemum virginianum begins in mid-Summer and lasts for approximately four weeks.

How to save seed from Pycnanthemum virginianum

About a month after blooming, the flowers will have formed seeds. Each individual flower will produce several tiny black seeds.

Pycnanthemum virginianum in Autumn. The seed heads are ready for harvesting.

To save seed, collect dried seed heads in Autumn or Winter, clipping them off and placing them into a brown paper bag. Store the bag out of direct sunlight in a cool dry place for a week to ensure the seed heads dry out.

After a week, you can crush the seed heads to release the black seeds. Use a fine kitchen strainer to separate the chaff from the seed. You can store the seed in an envelope or zip-lock bag for a couple of years.

Root system

The root system of Virginia Mountain Mint is fibrous and rhizomes. The rhizomes will extend out a short distance and eventually form a dense colony.

Related ==> Learn how to reduce the spread of rhizome plants

Grow and Care for Pycnanthemum Virginianum

Sunlight Requirements

Pycnanthemum virginianum will grow best in full sun (6+ hours of direct sun per day) or partial sun (4-6 hours of sun). The more sun you provide it, the larger and showier it will be.

Soil Requirements

Pycnanthemum virginianum is highly adaptable and will grow in almost any soil type from sandy to clay. This plant is not picky as to where it grows. [2]

Moisture Requirements

For moisture, Pycnanthemum virginianum does best in moist to average moisture conditions. It can survive occasional drought, but will become stressed.

Maintenance

The primary maintenance is to keep new plants in check. If this is planted in a formal flowerbed, be aware that there will be new shoots sprouting each Spring. In general you can use a spade to sever these roots in Spring, and stop the spread for that particular growing season.

Fertilizer

Virginia Mountain Mint should not require any supplemental fertilizer. As a native plant, it will grow just fine within it’s native range and growing conditions that it prefers.

Virginia Mountain Mint leaves turning yellow

If subjected to prolonged drought, the leaves of Virginia Mountain Mint will often turn yellow and fall off. So, yellowing of the leaves is a sign of drought. Should you notice this, provide supplemental water to the plant.

How to Grow Pycnanthemum virginianum from Seed

Pycnanthemum virginianum is one of the easier plants to grow from seed. The plant requires no special treatment, and the seeds need to be exposed to sunlight to germinate – so there is no ‘planting depth’! [7] [8]

Seeds of Pycnanthemum virginianum

Steps to grow Pycnanthemum virginianum from seed

  1. In early Spring, fill a container with moist potting soil. Leave a 1/2″ gap (12 mm ) at the top. Pack the moist soil firmly into the container.
  2. Sprinkle 5-10 seeds of Virginia Mountain Mint on top of the soil. Press the seed in with your finger.
  3. Keep the seeds moist using a spray bottle or pump sprayer by misting. Misting reduces the chances that the seed will wash out or accidentally get covered with dirt (remember, the seed needs sunlight!).
  4. Place the container in a location that receives morning sun and afternoon shade. This is important, as surface sown seeds have a tendency to dry out in afternoon sun. Water the seeds in the morning if required by misting.
  5. Germination should occur in mid to late Spring.
Pycnanthemum virginianum seedlings that I germinated in 2020

How to direct sow Pycnanthemum virginianum

To direct sow Pycnanthemum virginianum, you can simply broadcast or scatter seed in a disturbed or bare area anytime from Autumn through early Spring. Walk over the seed to make sure it has good contact with the soil. The seed will germinate once temperatures warm up.

Wildlife, Pests, and Diseases associated with Pycnanthemum virginianum

Pollinators

Get ready to see pollinators you’ve never seen before! Numerous species of bees, pollinating beetles, pollinating wasps, pollinating flies, and small butterflies are attracted to the nectar of Virginia Mountain Mint.

Pollinating Wasp on Pycnanthemum virginianum

Pests

Since the foliage produces such a strong minty aroma, the foliage is almost never eaten/damaged by deer, rabbits, or insects.

Deer and Rabbits

As a general rule, deer and rabbits will not eat Virginia Mountain Mint. The minty aroma and flavor leave a bad taste in their mouth. It is extremely rare for any herbivore to browse a member of the Pycnanthemum genus.

Disease

In general, Pycnanthemum virginianum is not effected by disease. It is a really tough plant. The only common issue is when it is exposed to drought the lower leaves turn yellow. This can be counteracted by watering the plant.

Where you can buy Pycnanthemum virginianum

Sometimes you can find Pycnanthemum virginianum in local Mom & Pop nurseries, but not in the big-box stores as it isn’t a typical ‘garden friendly’ plant. 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 Pycnanthemum virginianum

Pycnanthemum virginianum has multiple uses including ornamental, medicinal, culinary, herbal, and aromatic. [9]

Garden Uses

Pycnanthemum virginianum can look great in a wildflower garden, micro-prairie, meadow, or border planting. Anywhere that it’s spread can easily be controlled would be great too such as an isolated light pole, flag bole island, or mailbox.

Pycnanthemum virginianum blooming with Partridge Pea, Perennial Black-Eyed Susan, and Garden Phlox.

For formal flower beds, Pycnanthemum virginianum could be planted. But you would want to take measures to limit the spread like I outlined in this guide. It can help reduce the aggressiveness of the plant, but still allow it room to grow. Furthermore, the spread generally only needs to be controlled in the Spring. So, the maintenance aspect isn’t too high.

Companion Plants

Some nice companion plants that would look nice with Virginia Mountain Mint would include the following list of flowers that bloom concurrently, and like similar growing conditions.

Medicinal Uses

There are nine documented uses by three different Native American tribes. [10] Decoction of leaves were used for fever & chills. The flowers were used to flavor meat. An infusion was used to treat coughs. Flowers could be used as a stimulant to ‘rally a dying patient’. And a decoction of powdered root was used to stop menstrual cycles.

Essential Oils

The leaves of Pycnanthemum virginianum can be utilized in the production of essential oils.

Pycnanthemum virginianum is edible

Pregnant women should avoid consuming Pycnanthemum virginianum, as the native Americans found it had an effect on menstrual cycles. But, the flowers and buds of Virginia Mountain Mint are edible. The strong minty flavor can be used as a spice or garnish.

A tea can be made from the leaves (fresh or dried), but note that it is medicinal. It can cause sweating, flatulence, but is noted to generally restore health.

Find more native plants here

References:

[1] – (L.) Rob. & Fernald – Virginia mountain-mint, Virginia mountainmint Pycnanthemum virginianum. Integrated Taxonomic Information System Report. Accessed 15JAN2022.

[2] – Pycnanthemum virginianum. USDA Natural Resources Conservation Service. Accessed 16JAN2022.

[3] – Pycnanthemum virginianum. Global Biodiversity Information Facility. Accessed 16JAN2022.

[4] – Parker, Ingrid M., Shoshana K. Mertens, and Douglas W. Schemske. “Distribution of seven native and two exotic plants in a tallgrass prairie in southeastern Wisconsin: the importance of human disturbance.” American Midland Naturalist (1993): 43-55.

[5] – Hinds, H.R. 2000. Flora of New Brunswick : a manual for the identification of the vascular plants of New Brunswick. 2nd edition. Biology Department, University of New Brunswick, Fredericton. 699 pp.

[6] – Newmaster, S.G., A. Lehela, M.J. Oldham, P.W.C. Uhlig & S. McMurray. 1998. Ontario Plant List. Ontario Forest Research Institute, Sault Ste. Marie, Ontario. Forest Information Paper No. 123. 550 pp.

[7] – Loyd, Lydia Miramontes. “Fragmentation Effects On Fitness In Five Common Prairie Species.” Department of Biological Sciences, Eastern Illinois University. (2009).

[8] – MIRAMONTES, L., and SJ MEINERS. “Can assisted cross pollination be used to increase fitness in isolated plant populations?.” Biological Sciences, Eastern Illinois University. 2005. Accessed 16JAN2022

[9] – Essiential Oil – Setzer, William N., et al. “Essential Oils of Four Virginia Mountain Mint (Pycnanthemum virginianum) Varieties Grown in North Alabama.” Plants 10.7 (2021): 1397.

[10] – Pycnanthemum virginianum. North American Ethnobotany Database. Accessed 15JAN2022

Joe Foster

Hi - I grew up outdoors in nature - hiking, fishing, hunting. In high school I got my first job at a garden center where I learned to garden and landscape. I've been growing plants from seed and designing native plant gardens for over 10 years. I hope to share some of my knowledge with you! You may have seen some of my videos I create on our YouTube channel, GrowitBuildit (more than 10 million views!). You can find my channel here: https://youtube.com/@growitbuildit Additionally I am a wood worker / DIY enthusiast. I enjoy designing/building projects (with hand tools when I can!). I hope to give you some tips and useful information!

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