By Chrissy Moore

Recently, I traveled to Wyoming’s capital city, Cheyenne, for a long-anticipated holiday. While there, I had the opportunity to visit the Cheyenne Botanic Gardens (CBG), which served as a jumping off point for my exploration of the area. The garden started as the Cheyenne Community Solar Greenhouse in the late 1970s, but a new, grant-funded botanic garden opened at its current location in 1984. The approximately nine-acre facility is clearly very forward-thinking in how it manages the local climatic conditions, including how it displays the myriad plants that can handle Cheyenne’s brutal growing conditions—conditions found in few other places outside of the Cheyenne vicinity. If you have not been to Cheyenne, or its surrounding plains and mountains, I highly recommend that you visit. The landscape has so many unique features, many of which don’t become apparent until you get up close and personal—my favorite way to view plants.

Cheyenne sits at an elevation of 6,086 feet giving it its characteristic cold, semi-arid climate. On average, it receives a paltry 14 inches of rain per year—as I like to say, just enough to make you mad! Temperatures can swing wildly at any time of the year, from the upper 80s to mid-90s in summer down to the negative digits in winter. (Side note: CBG Director Scott Aker relayed to me that he left work at noon for an appointment when the outside temperature was 53° F. By the time he reached his destination 15 minutes later, the temperature had fallen to 3° F!). Most notably, Cheyenne is almost always windy: Winds average 30 – 40 mph at certain times of the year, or, if a good storm approaches, it is not unusual for blizzard/gale force winds to roar through town at speeds up to 100 mph. Have I mentioned the hail? Hail is a frequent threat during storms and does significant damage to herbaceous and woody plants alike, never mind your car or, God-forbid, a glasshouse! While I was there, a storm came through that produced hail the size of small tennis balls on one side of town; on the other side of town, a tornado threat was announced. For Cheyenne, it was “just another day that ends in ‘y’!”

As you might imagine, one would hardly consider these ideal conditions for growing most herbs. Maybe some plants could handle one or two of these conditions, but all combined…not so much. I spoke with the CBG’s supervisory horticulturist, Isaiah Smith, himself an Alabama transplant, who told me many people offer such helpful “suggestions” as, “Why don’t you grow Southwest plants?” Smith says with a smirk, “Because the Southwest is dry and low elevation. Cheyenne is dry at high elevation. They are not the same group of plants that can tolerate our extremes.” And he’s right, of course. Herb growers around the country and from different hardiness zones can attest to that. I’ve been told that basil can grow to three feet or more in some areas of Texas, whereas for our northerly friends, a short growing season and lingering cold temperatures during the shoulder months often cut basil’s lifespan in half compared to its southern counterparts.

As I meandered through CBG’s herb garden and hiked in the natural areas outside of Cheyenne, I was trying to keep a sharp eye out for what herbs—either native or introduced—I might recognize and which seemed to be the best performers. The native species in the Artemisia genus were clearly well-adapted to their environs. There was no shortage of Artemisia frigida (prairie sagebrush), which was historically used by the Cheyenne Indian tribe as a ceremonial herb. Sprigs of this plant were used in spiritual rites to petition for water and were tied to articles that were sacrificed to the sun. Although not a true sage (genus Salvia), it earned the name “women’s sage” by numerous tribes as the soft foliage was used for aiding menstrual hygiene, and the root was drunk in a tea to treat irregular menses (NRCS, N.D.). Its super-soft, silvery-green leaves are pleasant groundcovers in many areas.

Artemisia tridentata (big sagebrush), with its gnarly, woody branches and tiny three-lobed leaves, looked like old lavender plants scattered over the hillsides. It truly is ubiquitous in the region. “A. tridentata may be found mainly in cold deserts with powdery or sandy soil….[According to] Daniel Moerman’s Native American Ethnobotany lists, A. tridentata [i]s one of the ten plants with the greatest number of uses. Understanding the reason for this is easy after visiting the area: sagebrush is nearly everywhere. Tea was made from various parts of the plant, and it was used extensively in medicine. The wood was used as fuel, and the stringy bark was used in the manufacture of ropes and baskets” (Guana, N.D.).

Arctostaphylos uva-ursi (bearberry or kinnikinnik) is a plant we could never effectively grow in the National Herb Garden in Washington, DC, so we gave up long ago. And how could we have in the first place? Though the National Resources Conservation Service designates bearberry as a circumboreal plant and one that grows in many different situations, once I saw this absolutely glorious, shiny-green groundcover in one of its primary native environments—at a very dry 8000 feet elevation in the Vedauwoo Recreation Area of the Medicine Bow National Forest—I knew right then that we were dealing with a completely different scenario than what we have in DC. This is not to say these plants can’t grow elsewhere, as the NRCS points out, but trying to do so is a bit like Cinderella’s stepsisters trying to work themselves into the glass slipper—it just doesn’t fit…at least not very well. Arctostaphylos is most famous for its use in pemmican, an Indian foodstuff, but its leaves are also very astringent and can act as a vasoconstrictor, which some tribes dried, powdered, and applied to sores (Hart, 1976).

One of the most shocking herb-growing revelations was seeing the magnificent stand of French tarragon (Artemisia dracunculus var. sativus) growing with abandon in the CBG’s own herb garden. It is a plant given to many struggles in DC, but in Cheyenne, it looked like a rock star. The stand was huge and topped out around three feet! Tarragon is known for its culinary uses (see the Herb of the Month post for tarragon), so I’m not sure why it hasn’t been “lifted” yet (and I don’t mean that in the gardening sense) by some nefarious foodie. Don’t get any ideas! I was immediately jealous of the CBG’s ability to grow this plant, since it’s such an herbal icon, but we can’t have everything, now, can we?

Some of the old standbys like oregano, foxglove, comfrey, sage, catnip, costmary, and valerian also grew like gangbusters in their herb garden, which, admittedly, was in a slightly protected location. But, you can’t really avoid 40 mph winds and hail the size of a small child no matter how hard you try. So, we should give credit where credit is due. Surprisingly, lavender also made an appearance but was a little less appreciative of its location. Who could blame it, really? Cheyenne’s version of a dry climate isn’t exactly the same as the French Mediterranean version.

During this trip, my appreciation for those intrepid gardeners, professional or otherwise, who take on the challenge of places like Cheyenne—one of the most extreme environments in the country—went up exponentially. Whether you’re hiking through natural areas or strolling in the manicured gardens of a horticultural institution, successfully growing tough, weather-tested herbs in the high plains, no matter the genera, is a heroic effort few people are willing to embrace. Just ask Isaiah and his coworkers! In Cheyenne, though, and specifically at the Cheyenne Botanic Gardens where they showcase what is possible for all who visit, extreme conditions are all in a day’s work. My hat goes off (no pun intended) to all those high plains heroes whose capes we see whipping around in the prairie wind!

Medicinal Disclaimer: It is the policy of The Herb Society of America, Inc. not to advise or recommend herbs for medicinal or health use. This information is intended for educational purposes only and should not be considered as a recommendation or an endorsement of any particular medical or health treatment. Please consult a health care provider before pursuing any herbal treatments.

Photo Credits: 1) Cheyenne Botanic Garden entrance planting; 2) “Wyoming Wind Sock”; 3) Artemisia frigida (prairie sagebrush); 4) Artemisia tridentata (big sagebrush) and Castilleja linariaefolia (Indian paintbrush); 5) Arctostaphylos uva-ursi (bearberry/kinnikinnik) and Artemisia tridentata as groundcovers in the Vedauwoo Recreation Area; 6) Artemisia dracunculus var. sativus (French tarragon) at Cheyenne Botanic Garden; 7) Tanacetum balsamita (costmary), Salvia officinalis (garden sage), Lavandula angustifolia (English lavender) at the CBG; 8) Master Gardeners visiting the CBG. All photos courtesy of the author except the “Wyoming Wind Sock” (public domain).

References

Gauna, Forest Jay. N.D. Plant of the Week: Artemisia tridentata. United States Forest Service. Available from: https://www.fs.usda.gov/wildflowers/plant-of-the-week/artemisia_tridentata.shtml. Accessed 9/18/2023.

Hart, J. 1976. Montana–native plants and early peoples. Helena, MT: Montana Historical Society. 75 p.  

Natural Resources Conservation Service Plant Guide. N.D. Bearberry (Arctostaphylos uva-ursi). United States Department of Agriculture, National Plant Data Center. Accessed 9/18/2023.

Natural Resources Conservation Service Plant Guide. N.D. Prairie sagewort (Artemisia tridentata). United States Department of Agriculture, National Plant Data Center. Accessed 9/18/2023.

Chrissy Moore is the curator of the National Herb Garden at the U.S. National Arboretum in Washington, DC. Aside from garden maintenance in the NHG, Chrissy lectures, provides tours, and writes on various herbal topics. She serves as co-blogmaster of The Herb Society’s blog, is a member of the Potomac Unit of The Herb Society of America, and is an International Society of Arboriculture Certified Arborist. When not doing herbie things, she can be found looking after many horses.