Cheyenne Garden Gossip

Gardening on the high plains of southeastern Wyoming


Fair flowers educate

2017-09 Floriculture Dept by Barb Gorges

The Floriculture Department at the Laramie County Fair includes perennials, annuals, herbs, potted plants and flower arrangements. Photo by Barb Gorges.

Published in the Wyoming Tribune Eagle Sept. 17, 2017 “Fair gives lesson about best oflowers to grow locally.”

By Barb Gorges

I wasn’t thinking of our county fair being a learning opportunity until I overheard one woman visiting the floriculture department say to another, “You should try that in your garden.”

I realized then that the open class entries (all the entries that are not 4-H or FFA) could tell me a lot about what Laramie County gardeners grow, and grow well, at least at the beginning of August.

Checking the fair results at http://www.laramiecountyfair.com, in horticulture (fruits and vegetables), there were only 81 entries, indicating a growing season with a slow, cold start. However, for floriculture [starting on page 148], there were many more entries: perennial flowers (146), annual flowers (84), culinary herbs (64). The other categories, flower arrangements, dish gardens and potted plants, had a total of 55.

Why wouldn’t you plant perennials, the most popular category, in the first place? They take so little work once established. And once you’ve planted a perennial, why wouldn’t you snip three identical flowers the first week in August, place them in a clear glass jar, carry them to the fair and hope for a blue ribbon and $6 premium?

I’ve entered numerous quilts in fairs over the last 35 years (one to two hundred hours or more of work for a chance at the same $6 premium) and understand quilt judging, but I wasn’t sure what floriculture judges were looking for.

The fair book will tell you a little bit, but the 2017 edition is no longer available and the 2018 edition won’t be on the website until next spring. You can contact the Floriculture Superintendent, Chris Wright, through the fair office, 307-633-4670, if you have questions now.

Unlike other competitive endeavors, fair judges give out as many blue ribbons in any class as they feel are warranted. The entries are judged by how well they represent the class. For instance, all seven pansy entries received blue ribbons. However, all the Monarda (beebalm) entries received red ribbons and only $4 premiums.

I chatted with one of the two floriculture judges afterwards. Chris Hilgert, Wyoming Master Gardener coordinator and Extension horticulture specialist, explained he thought all the beebalm was a little past its prime.

Beebalm flower heads are made up of tiny florets that bloom in groups, one concentric ring at a time. Mine had already been in bloom five weeks. But pansies have no florets, just five petals per flower. Mine have been putting out fresh flowers nearly every day since they started blooming in April.

Hilgert has been judging several fairs a year for the last 14 years. He looks for entries that are healthy—no sign of disease or pests. You can pinch off bad leaves, but you can’t remove very many bad flower petals without ruining a bloom.

The containers don’t matter, Hilgert said, though he prefers that they be a size matching the stem length. He’d rather not fish flowers out of the water when they fall into too tall vases. Our fair’s rules call for clear glass or plastic containers and it doesn’t matter to Hilgert whether they are vases or just jars and bottles.

2017-09 Rudbeckia entry by Barb Gorges

Rudbeckia entry in a jelly jar gets a blue ribbon. Photo by Barb Gorges.

When a class description asks for three stems, or three blooms, the three need to be as uniform as possible: same size flowers, same length stem, and flowers at the same stage of bloom. This year I had a bumper crop of Rudbeckia (gloriosa daisy or black-eyed susan), but in over 100 blooms, only three were identical, and luckily, were fresh enough to last the whole week of the fair.

Avoiding wilting, another of Hilgert’s benchmarks, was easy this year—it was a cool, rainy day when we brought our entries to the Exhibition Hall. However, during hot weather, the fair’s rules stating that all open class entries must be turned in between noon and 8 p.m., but not judged until the next morning, doesn’t work well for the tender plants. And it is another day before the public can view them. Volunteers keep the containers of flowers and the potted plants watered during fair week.

There is a simple strategy for entering floriculture at our fair. Before the entry deadline at the end of June, put in online for every class for which you have something planted. There is no entry fee. No one can predict what will look best the beginning of August when the flowers need to be picked. While seven people had great Shasta daisy entries this year, mine were already finished blooming. Of the 35 classes I put in for, I only brought 14 entries. I didn’t even have hail damage this year. It was just a matter of bloom timing.

There is a competitive aspect to the Floriculture department—those other awards that give you bragging rights: Superior, Best of Show, Reserve Champion and Champion. Those are the purple ribbons, some with fancy rosettes, that transcend the classes.

This year gardeners were rewarded with them for an exceptional hybrid tea rose, a sunflower, a salpiglossis, two mints, three potted plants and a fairy garden. A truly wonderful flowering tuberous begonia, entered by one of my neighbors, Jean Profaizer, was the champion.

Whether you ever intend to enter the fair and make some “seed money,” it is worth reading the Floriculture results to see what can bloom in Cheyenne in late summer. I counted over 20 kinds of culinary herbs (although these don’t need to be in bloom), 16 kinds of annuals and 30 kinds of perennials. The most popular, if you put all four classes of it together (white, yellow, pink and other), was yarrow, with 25 entries. It happens to be an easy perennial to grow, too.

2017-09 Echinacea entry by Barb Gorges

Echinacea is another popular fair entry because it is in bloom in early August. Photo by Barb Gorges.

Other late summer standbys are Echinacea (coneflower), Gaillardia (blanket flower), daylily, lilies, various roses, violets, and as previously mentioned, Rudbeckia.

Among the annuals are geranium, cosmos, bachelor buttons, snapdragon, sunflower, marigold, petunia and pansy (though my pansies sometimes come back, acting like short-lived perennials).

When you walk through the display of flowers at our fair, each vase or jarful with its entry tag that you see gives you more familiarity with local possibilities. If you are lucky, the gardener has added the variety name—it’s supposed to give them extra competition points.

With all that information, now is the perfect time to assess your garden, make plans and gather or order what you need for next season. Any end of the season sales on perennials at nurseries? How about seeds, both flower and vegetable? Although they are never seen at the fair, don’t forget spring-blooming bulbs. And think about planting flowering trees and shrubs.

The downside? You may have to dig a new bed to accommodate all your future flower plans. But the bees, birds, butterflies and bats thank you.

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The Mint Family

Photos courtesy of Jane and Robert Dorn. Hover over image for name of plant.

Skullcap, Scutellaria brittonii, 8 inches tall, native perennial found in rocky and gravelly places.

Coyote mint or mountain beebalm, Monardella odoratissima, 12 inches tall, prefers moist places in full sun.

Horsemint or purple beebalm, Monarda fistulosa, and cultivars, 2 feet tall, easily found in area nurseries. Transplants easily.

Giant (or anise) Hyssop, Agastache foeniculum (also called hummingbird mint),  3 feet tall, blooms July through September. Found for sale at nurseries.

Published in the Wyoming Tribune Eagle Feb. 19, 2017

Introducing the mint family: from here, there and everywhere

By Barb Gorges

I was thinking a good winter pastime would be to research the mint family, Lamiaceae of which there are 7,500 species. I found tales of the good, the bad and the ugly.

Some mints were invited over to the New World because they were thought to be good garden plants, capable of providing medicinal uses, if not culinary flavor.

But some of them escaped the picket fences, becoming weeds that hang out on the dusty edges of civilization. Some poisoned livestock. Others just didn’t fit in the preferred landscape and have been periodically eradicated, especially the ones that insist on infiltrating the monoculture of lawn.

New World natives, while never originally confined to the cultivated garden, were valued for their medicinal know-how, but over time some recipes have been lost. They have been admired for their beauty and ability to thrive, each in its favorite wild place, providing sustenance to the local wildlife population. Only recently have we invited them into our cities and towns. But often we expect them to be made over into a showier version of themselves.

No matter where mints are from, they almost always share square stems and opposite leaves and they smell nice when you brush against them or crush their leaves.

Well-established garden mints

Immigrating people often take along their favorite plants from home. A surprising number of our favorite cooking herbs we grow in Cheyenne are mints that have travelled:

–Basil, Ocimum basilicum, traces its roots to India but is important to many cultures from Mexico to southeast Asia;

–Spearmint, Mentha spicata, Europe and Asia;

–Peppermint, Mentha x peperita, Europe and Middle East;

–Oregano, Origanum vulgare, Eurasia;

–Sweet marjoram, Origanum majorana, Middle East;

–Rosemary, Rosmarinus officinalis, Mediterranean;

–Garden sage, Salvia officinalis, Mediterranean;

–Common thyme, Thymus vulgaris, Europe;

–Lavender, Lavandula angustifolia, Mediterranean;

–Lemon balm, Melissa officinalis, Europe, Iran, Central Asia.

Garden mint turned weed

Horehound, Marrubium vulgare, is considered a medicinal herb, but has escaped cultivation. Originally from Europe, North Africa and Asia, it is now listed in the handbook, “Weeds of the West,” because it has invaded our native grasslands, including here in southeast Wyoming. Wherever there is a disturbance in the natural landscape, look for it. It’s considered a weed because it is unpalatable to livestock.

Robert Dorn, in his book, “Vascular Plants of Wyoming,” lists other weedy mints in our county:

–Creeping Charlie, Glechoma hederacea, Eurasia, common in lawns, attracts bees, has been used in beer and cheese making, but is toxic to cattle and horses;

–Dead nettle, Laminum amplexicaule, Eurasia and North Africa, problem in croplands and newly seeded lawns though one variety is considered good landscape ground cover;

–Motherwort, Leonurus cardiaca, Eurasia, an herbal remedy, introduced for bees, now invasive;

–Lanceleaf sage, Salvia reflexa, Eurasian ornamental, listed in “Weeds of the West” because it is poisonous to livestock when chopped into or mixed with other feed.

Exotic and native mints excel

But here’s a good mint that has become a naturalized in Laramie County and elsewhere in North America: catnip, Nepeta cataria. It is native to Eurasia and Africa. A hybrid, Nepeta x fassennii, known as garden catmint “Walker’s Low,” became the perennial plant of the year in 2007.

For every difficult mint, there are more mints that contribute positively to society. Here at the north end of the Front Range, and elsewhere in the drylands of the west, we are looking for plants for our gardens that don’t need much water. Some of those are natives and others from similar landscapes on the other side of the world.

Take Russian sage, Perovskia atriplicifolia, straight from the steppes of central Asia. It’s become extremely popular around here, plant it and forget it, but I don’t think anyone has taken advantage of its Old World reputation as a medicinal, or put the flowers in salad or crushed them for dye.

Water-frugal homeowners are replacing lawn with various creeping thymes, Thymus spp., and all of them hail from Europe, North Africa or Asia.

Horticulturists are always working on improvements and a catalogue like High Country Gardens shows examples. You’ll notice cultivars (cultivated varieties) with cute names. The improvements can be better cold tolerance, better drought tolerance, longer blooming and or bigger, brighter blooms. Some species are native to Turkey, like a type of lamb’s ear, Stachys lavandulifolius, or another from Arizona, another lamb’s ear, Stachys coccineus.

Wyoming natives

What I am more interested in meeting these days are the Wyoming natives, the plants that know how to get along with the native wildlife, including birds, bats, bees, butterflies, and other insects.

Looking again at Robert Dorn’s book, among the mints found in southeast Wyoming I saw:

–Dragonhead, Dracocephalum parviflorum;

–Drummond’s false pennyroyal, Hedeoma drummondii (used as a minty flavoring in Mexico);

–False dragonhead, Physostegia parviflora (related to obedient plant);

–Selfheal, Prunella vulgaris (a common lawn “weed” and Holarctic native—native to northern areas around the globe);

— Canada germander, Teucrium canadense.

Cultivated natives

These plants don’t show up in Dorn’s book he coauthored with his wife, Jane: “Growing Native Plants of the Rocky Mountain Area.” It could mean they aren’t showy enough or perhaps too difficult to grow. *

However, Dorn and Dorn mention these other Rocky Mountain mint cousins for our gardens:

–Giant (or anise) hyssop, Agastache foeniculum, also called hummingbird mint;

–Horsemint or purple beebalm, Monarda fistulosa;

–Coyote mint or mountain beebalm, Monardella odoratissima;

–Skullcap, Scutellaria brittonii.

Problem family members

Some gardeners have banned all mints from their gardens because they have heard they spread uncontrollably. That is true in my experience with the mentha species.

My chocolate mint, Mentha × piperita ‘Chocolate Mint,’ was well-behaved for 10-15 years until the summer I pruned back the big rosebush nearby and gave it more sun. It went ballistic. By fall I was ripping it out with my bare hands. Standard advice has been to keep crazy mints in pots so they can’t spread.

My lemon balm goes to seed before I notice and seedlings pop up the next year, but it never complains when I dig it up to share and make room for other plants.

Live and let live

The old-time culinary mints share my same raised bed and keep each other in check. Even the Russian sage hasn’t gotten out of hand as it would in a more open spot.

Maybe it’s time to try some of those new native cultivars and spice things up—and see what the bees think.

Note:

To see photos of these plants, search https://plants.usda.gov or Wikipedia, using the scientific names.

*To see Jane Dorn’s list of 25 native plants recommended for Cheyenne gardeners, and to purchase the digital version of “Growing Native Plants of the Rocky Mountain Area,” visit https://cheyenneaudubon.wordpress.com/habitat-hero/.


Perennial fall flower color

2016-10-yampa-river-botanic-park-steamboat-springs-co-sept-8-2016-by-barb-gorges

Yampa River Botanic Park, Steamboat Springs, Colorado, Sept. 8, 2016. Photo by Barb Gorges.

Published Oct. 9, 2016, Wyoming Tribune Eagle, “Fall color for next year’s perennial flowerbeds.”

Find fall color for next year’s perennial flowerbeds (full version)

Text and photos by Barb Gorges

In September, I had the opportunity to visit three public gardens: Chanticleer near Wayne, Pennsylvania; Berkshire Botanical Garden in Stockbridge, Massachusetts; and Yampa River Botanic Park in Steamboat Springs, Colorado.

What struck me was the colorful perennial flowers that were blooming in the fall. Of course, not everything that grows outside Philadelphia grows here in Cheyenne where we are two Plant Hardiness Zones colder, Zone 5.

We match the western Massachusetts mountains for zone, but they get four times our 15 inches of annual precipitation. Plus, they have acidic soils supporting those billowing mounds of hydrangeas I saw everywhere.

Even in Steamboat, only 700 feet higher in elevation, there are plants that require the protection of a thick layer of snow all winter which we don’t have.

So I decided to look around town, especially our own Cheyenne Botanic Gardens, to see what blooms late, for the benefit of bees and our own enjoyment.

Annual flowers are colorful right up to first frost, average date Sept. 20 (though in the last few years in some parts of town it may be as late as mid-October). But unless they self-seed, I can’t justify buying flats of annuals every spring to cover all my garden beds, nor have I the greenhouse to start my own. Instead I turn to perennials. Here are suggestions for you to add to your garden next spring. Or if we haven’t had a frost yet, find them on sale and plant them this fall.

2016-10-1-rudbeckia-by-barb-gorgesI’ve done well with black-eyed Susan, Rudbeckia species. Their golden yellow petals and brown centers must have inspired the University of Wyoming’s selection of school colors. There are many varieties based on native species: short or tall, diminutive or gigantic flowers, mid-summer bloomers or later. Some bloom a long time—over a month. Some are better at coming back year after year.

2016-10-2-aster-by-barb-gorges            My other success has been the fall-blooming asters, Symphyotrichum species. One variety is a 2-foot-tall shrub of lavender-colored, 1-inch flowers. It’s come back every year for over 20 years, waiting until mid-September to bloom. But another, brighter purple aster in a sunnier spot started blooming three weeks earlier and is still blooming well. Perhaps it is a newer variety bred for a longer bloom time than the native plants.

I hesitate to give you actual variety names because nurseries so often move onto the next best thing. You might as well go for what’s available rather than mourn what you can’t find. However, if you are interested in native perennials, check sources like www.alplains.com.

2016-10-3-gaillardia-by-barb-gorges            Blanket flower, Gaillardia species, is another hard-working perennial native to North America. It can start blooming in early summer. Horticulturists have had a field day designing varieties with different color patterns. A member of the aster family, it has petals that can be plain yellow, yellow with bands of red, or nearly all red-orange with a little yellow trim. Some are short, some tall. The seed heads are prickly little balls. If you deadhead them when they are finished blooming, they will put out more flowers. If you don’t, they will drop seeds that will sprout next year, like many other easy-to-grow perennials.

2016-10-4-hollyhock-by-barb-gorges            I’ve noticed that some of my summer bloomers will bloom into fall if I water them enough. I have a bed with a row of hollyhocks growing along the back. It gets watered by a sprinkler head that does a good job at one end but hardly gets water to the other end. Thus, the hollyhocks on the dry end finished blooming a month before the hollyhocks on the wet end.

2016-10-5-salvia-by-barb-gorges            Perennials that bloom in early summer may start blooming again in early fall—perhaps they don’t like hot mid-summer temperatures. I’ve had ‘Hot Pink’ Salvia, Salvia gregii, come back into bloom this year.

Microclimates make a big difference as to when perennials bloom. Nettie Eakes, assistant education director at the Cheyenne Botanic Gardens’ Paul Smith Children’s Village, said visitors are always telling her how the same flower in their yard is either behind or ahead.

The Children’s Village is lucky to be protected by high stone walls. On their north-facing sides, they provide shade and make a cool, slow-growing microclimate. On the south-facing sides, they absorb sunlight and make a warmer, faster-growing microclimate which can also extend the growing season.

2016-10-6-sneezeweed-by-barb-gorges            The most noticeable perennial I found blooming September 18 at the Children’s Village was sneezeweed, Helenium autumnale, a 6-foot-tall plant with multiple small sunflower-type flowers, each with yellow petals and ball-shaped yellow centers. Nettie said they increase by sending out underground stems, but are not very invasive. Helenium comes in many other variations and bloom times.

2016-10-7-giant-hummingbird-mint-by-barb-gorgesOver by the office door, three-foot tall giant hummingbirds mint, Agastache pallida ‘barberi’, does not have shout-out-loud color. But it is a nice contrast: silvery spikes of tiny purple flowers. And maybe it will attract a late hummingbird—or hummingbird moth.

2016-10-8-karl-foerster-grass-by-barb-gorgesAt the front entrance to the Children’s Village is ‘Karl Foerster’ feather reed grass, Calamagrostis acutiflora ‘Karl Foerster’. It’s a go-to plant for landscape designers these days, but that’s because it looks so neat. Growing around four feet tall, it starts out green in summer. Then the seed heads ripen to a golden wheat color. Finally, the whole plant turns gold. It is tough enough to stand and provide color all winter before getting cut back in spring.

2016-10-9-russian-sage-by-barb-gorgesA wispy, shrubby perennial also favored by landscape designers in our area is Russian sage, Perovskia atriplicifolia. Each branch sprouts from ground level, with silvery leaves on the lower half and small blueish lavender flowers on the upper half of each stem. It likes sunny spots and will spread.

Chatting with my Laramie County Master Gardener friends, Steve Scott and Kathy Shreve, I also have this list of fall bloomers for you to think about planting next year:

2016-10-10-autumn-crocus-by-barb-gorgesAutumn crocus, Colchicum species. Corms are planted in July or August. The blossoms are much larger than spring crocus.

Blue sage, Salvia azuria, native to central and eastern North America.

2016-10-11-goldenrod-by-barb-gorgesGoldenrod, Solidago species, blooms are branches of tiny yellow flowers. Many are native to North America.

2016-10-12-joe-pye-weed-by-barb-gorgesJoe Pye weed, Eutrochium species, another North American native, sometime varieties are 5 feet tall, with panicles of purple-pink flowers.

2016-10-17-maxmillian-sunflower-by-barb-gorgesMaxmillian sunflower, Helianthus maximiliani, native to the Great Plains, 2 to 10 feet tall, branches with many yellow flowers.

2016-10-13-purple-coneflower-by-barb-gorgesPurple coneflower, Echinacea purpurea, daisy-like, native to North America, many varieties, 1 to 4 feet tall.

Snakeweed, Gutierrezia species, a shrub with yellow flowers native to western North America.

2016-10-14-rabbitbrush-by-barb-gorgesRabbitbrush, Ericameria nauseousus, or Chrysothamnus viscidiflorus. Both are yellow-flowered shrubs. The native varieties grow on our drier prairies.

2016-10-15-autumn-joy-sedum-by-barb-gorges‘Autumn Joy’ sedum, Sedum telephium, is a stonecrop. The fleshy stems grow 1-2 feet tall, topped with bunches of tiny purple-pink blossoms. It can be found in the Cheyenne Botanic Gardens perennial bed.

2016-10-16-obediant-plant-by-barb-gorgesObedient plant, Physostegia virginiana, looks like a 2 to 4-foot-tall snapdragon with pale lavender-pink flowers. It is also at the Gardens.


Starting from Seed: Choosing the Right Seed

Short season seeds

Some short growing-season vegetable choices for Cheyenne

Published Feb. 26, 2012 in the Wyoming Tribune Eagle, “From scratch: A beginning gardener shares her experiences gained from taking the first steps in growing indoor tomato plants from seed.”

By Barb Gorges

Can I call myself a gardener if I buy blooming bedding plants and keep them alive until frost?

Possibly. But my real test is whether I can start something from seed indoors, which I haven’t done in 20 years. And, even though it’s February, now is not too early to start thinking about that.

My inspiration is the pep talk Kathy Shreve and Barb Sahl gave the Master Gardeners’ class recently. It looks so simple: florescent shop light, sterile seed-starting medium and pots, proper watering, a little air circulation and fresh seed.

Seed. There’s the sticky spot. Some plants I like don’t do well in Cheyenne or would need more sun than my shady yard offers.

This is my experiment for the coming growing season: raise from seed at least one easy annual flower and a fast tomato.

Why all the bother? Because just as I can bake my own bread, even though it’s much easier to buy a loaf at the bakery, I want to see if I can grow from scratch.

Seeds

There are several seed companies out there that cater to our unique gardening needs.

For starters, I was already familiar with Maine’s Pinetree Garden Seeds. This company offers a reasonable climate match. I ordered from them years ago and Shreve does today. Visit www.superseeds.com or call 207-926-3400.

Shane Smith, director of the Cheyenne Botanic Gardens, mentioned three seed catalogs recently that match other aspects of our challenging growing conditions.

For high altitude, try Seeds Trust, located in Littleton, Colo., www.seedstrust.com, or call 720-335-3436.

For drought-hardy plants, High Country Gardens in Santa Fe, N.M., offers recommendations on xeric gardening, as well as plants and seeds. Visit www.HighCountryGardens.com, or call 800-925-9387.

For a comprehensive flower and vegetable catalog, check Johnny’s Selected Seeds, which is another Maine company. Visit www.johnnyseeds.com or call 877-564-6697.

You can also check local garden centers, but do read the seed packets carefully.

Unfortunately, I don’t think anyone specializes in plant varieties that are hail and wind resistant.

Planting strategy

For my summer project, Wissner recommended I start with a cherry tomato plant. The fastest tomato I could find, maturing in 55 days, is called Gold Nugget, which produces yellow cherry tomatoes.

Local gardeners who want to grow tomatoes might want to look for tomatoes that mature in 55 to 60 days, she said. This means with luck, you’ll harvest your first tomato 69 to 80 days after May 25–that is, between Aug. 2 and 13. The average first frost date looms barely more than a month later, about Sept. 20.

Why all the extra time? Vegetable seed packets and catalogs will tell you how many days it takes for seeds to germinate and how long until harvest time. In reality, you need to extend those time frames by many days, Wissner said.

When Wissner starts vegetables indoors, she first adds another 14-20 days after germination to allow plants to grow to transplant size.

She then adds another 14 to 20 days after transplanting outdoors. That accounts for transplant shock. At that point, she can start counting the stated days to maturity.

For my annual flower, Wissner recommends cosmos, which produces brightly colored flowers.

The cosmos I’ve chosen, a dwarf variety in a mix of colors, germinates in seven to 10 days. Maturity is at least 75 days for some cosmos varieties so if I want flowering plants to put out in May, seeding indoors the first of March might not be too soon to start. But since even dwarf cosmos could be 2 feet tall at flowering, they’d get too big for my set-up, so I’ll wait a bit.

And both the flowers and the tomato will need “full sun,” –at least 6 hours per day. I’ll have to think about where to fit them in my shady yard, or which tree to cut.

It’s easy to see why buying well-developed plants from the nurseries is so popular when, for instance, some varieties of tomatoes are rated at 120 days to maturity, the number of days after seed germination before the first fruit can be harvested.

Next month I’ll prepare my seed-starting equipment. Digging in the garden is still months away, even if wind keeps evaporating the snow.

Climate

The first hurdle to choosing plants that will thrive in your yard is understanding the climate.

The newly revised USDA Plant Hardiness Zone Map (http://planthardiness.ars.usda.gov) shows Cheyenne in Zone 5b, meaning our maximum cold temperatures are -15 to -10 degrees Fahrenheit. Because of our 6000-foot elevation and northern latitude, we also have a short growing season.

Cheyenne’s average first frost-free date is May 25—that’s considered a safe time to get your plants in the ground.

After that, the growing season is only 90 to 110 days long, according to Catherine Wissner, University of Wyoming Laramie County Extension Service Horticulturist.

You can see why season extenders like Wall O’ Water, hoop houses or high tunnels— modern, light-weight greenhouses—are popular here. They can push the planting date earlier by weeks.

Note: Using Catherine’s formula and the catalog information, I figure I’ll need to plant the seeds four to six weeks before May 25, in early April. If I decide to try Wall O’ Water, giving each plant its own little protective, water-filled, plastic walls so that I can transplant them earlier, I will have to start seeds earlier.