The Good Guys: Native Thistles

Cirsium scopulorum_Frosty Ball_SummitLakeMtEvans-CO_LAH_5720

Last month I wrote about Scotch Thistles, a noxious weed in Colorado and in many other states. Then there are Bull Thistles, Musk Thistles, Plumeless Thistles, and Canada Thistles, also on the Colorado noxious weed list. This begs the question, are all thistles invasive, nasty plants, or are there some good guys among them?


Applauding Leadplant

Amorpha canescens_Leadplant_DBG_LAH_0251

Sometimes I think of leadplant (Amorpha canescens) as the ugly duckling of xeric shrubs. It’s just not appreciated. Consider this quote from the Missouri Botanic Gardens (MBG) webpage:

A somewhat ordinary looking, small shrub with an attractive bloom but otherwise with no particularly outstanding landscape features. Good plant for naturalizing in a native or wildflower garden, prairie or meadow.


Fabulous Four O’clocks

Mirabilis multiflora - Desert Four O'clock @XG 9aug05 LAH 080 printIn a field crowded with contenders, I have a new favorite wildflower. This plant is incredible—large, flashy, tough, gorgeous. What more could you want? Best of all, it’s thriving in my yard. I’m in love.

Most four o’clocks are sedate, old-fashioned garden flowers, something you’d see surrounding a cottage, combined with hollyhocks, old roses, and other grandmotherly plants. The Desert Four O’clock (Mirabilis multiflora) is like the grandma who dies her hair brilliant pink, wears short skirts with black fishnet stockings, and rides a Harley.


Colorful Columbine

Aquilegia hyb_Columbine_Silverton-CO_LAH_5115Envision a woodland garden, and nodding columbine are one of the first plants that comes to mind. With their intricate shapes and rainbow of colors, columbines are deservedly popular perennials.

The original North American columbine species (Aquilegia viridiflora) crossed the Bering Strait from Eurasia, migrating across the land bridge that once connected the two continents. From there, the plants expanded into new territory, evolving into new species as they moved southward. Now there are columbines adapted to every habitat from cool, high mountain meadows to burning deserts. This diversity is a boon for flower lovers; no matter where you live, there’s a columbine for your garden.


Castilleja miniata Paintbrush

Castilleja - Indian Paintbrush__SpruceGrove-Tarryall_20090626_ 0038)The scarlet blossoms really do look like bushy paintbrushes dipped in red paint; they’re hard to miss, even in a meadow crowded with wildflowers. Most of us easily identify these iconic perennials, although we may be a bit confused by the species that bloom in pink, white, and yellow.

Here along the Front Range of Colorado, the most common species of paintbrush is Castilleja miniata, more familiarly known as Giant Red Paintbrush. The one- to two-foot plant is easily identified by its long, unbranched stems lined with lance-shaped leaves. They’re topped with colorful bracts, which are usually divided into threes. These bracts are typically red (miniata means “colored red”) but you can also find blooms in shades of orange, salmon, and pink. The actual flowers are yellowish-green tubes that grow to become more visible later in the season.


Heavenly Blue Wildflowers

Blue Flax_Durango-CO_LAH_2356Who doesn’t like blue? With clouds of sky-blue, 5-petaled flowers that seem to float among the surrounding foliage, Blue Flax is a welcome addition to any garden. A perennial hardy to 9,500 feet, the fountain-shaped plants are comprised of graceful, wiry stems reaching two feet in height, and embellished with blue-green needle-like leaves.

Flax’s open, airy stems tend to go unnoticed, but the abundant true-blue flowers will fill those empty spaces between more vibrantly colored blooms in a perennial border. However, flax is most at home naturalized into a grassy meadow, where it can mingle with blue gramma grass and other short-grass prairie wildflowers.



Delphinium_ColoSpgs-CO_LAH_4854-001Most people recognize Delphiniums in the cottage garden. With their tall spikes of vibrant blue (or red, pink, rose, white, orange, or purple) flowers, nothing else is quite like them. Huge delphiniums are a staple in England, where cool temperatures and fog provide a perfect environment. But I despaired of having these heavenly blue blossoms in my Colorado garden. It’s just too hot and dry.

Colorado gardeners do manage to grow spectacular hybrid Delphiniums, but as one Colorado master gardener put it, a delphinium is

“… one of the neediest perennials ever. It likes sun but not in the hottest part of the day. It needs even moisture, mulching and careful watering. It reacts poorly to extremes of heat and cold, and requires a lot of fertilizer. To top all that, it requires its devoted fans to cut it back immediately after early-summer flowering before it will even consider reblooming a full three months later. (Many years, early June bloom is all you get, given the extreme pickiness of this flower.) Finally, unless it really, really likes its location, it may never be seen again after that September curtain call.”

Delphinium @CSUtilXeriscapeGarden 9Aug2006 LAH115I’m not that dedicated to fussing over a particular plant, no matter how gorgeous, which is why I was delighted to discover that the familiar, tall Delphinium grandiflorum isn’t the only kid on the block. Other cultivars and species are much better adapted to our challenging conditions.

Blue Butterflies (right) is a cultivar of D. grandiflorum, but you’d never recognize it. Growing only one to one-and-a-half feet high, these bushy plants are covered with purple-blue flowers that are more open than the Giant Pacific Hybrids. Instead of big leaves, the foliage is finely divided, giving it a lacy look. You still need to provide moist, rich soil, and they need to be deadheaded, but at least they survive a windy day much better than the staked varieties. My Blue Butterflies did eventually die, but it lived for several years without any special attention on my part. I was impressed.

Delphinium_exaltatum wikicommonsDelphinium exaltatum  (left, photo courtesy of Wikicommons) is a perennial species native to the eastern U.S. As you might expect, it must be kept constantly moist, but it tolerates Colorado’s lime soils. Plant in morning sun or bright shade (it needs full sun where skies are often overcast) and provide protection from strong winds. Fertilize regularly. As they fade, remove the flower spikes to encourage additional bloom (maybe). You can buy seedlings or start your own; a cold treatment is needed for germination.

Delphinium x belladonna is another hybrid perennial that is easier to grow. It prefers full sun, well-drained soil with high fertility (amend, amend!), and shelter from strong winds. It’s a good idea to stake the tall flower spikes. This delphinium originated in Europe. It’s best to buy transplants.

Delphinium hyb_BFAlpineGarden-Vail_LAH_4851-001We haven’t mentioned pests and diseases yet, but there are plenty of both. Delphiniums are susceptible to powdery mildew, southern blight, root and crown rot, botrytis blight, fungal and bacterial leaf spots, white rot, rust, white smut, leaf smut, and damping off. Slugs love them, although that’s not a huge problem in Colorado. They also get cyclamen mites, borers, and leaf miners. To top it off, all parts of Delphinium plants are poisonous; even handling the plants can cause skin irritation.

Given the difficulty of growing your own, perhaps a better solution is to enjoy the delphiniums that Mother Nature grows. An easily-recognized wildflower (it’s the tall, blue or purple one), most wild delphinums are annuals, and are referred to as Larkspur. The Colorado Rockies offer several species. One good location is Crested Butte in mid-July, or try Yankee Boy Basin above Ouray (4-wheel drive needed).

Seeds for Colorado

Glass Gem Corn. Photo: Seeds Trust Facebook page
Glass Gem Corn. Photo: Seeds Trust Facebook page

I love getting seed catalogs in the mail. The flowers are so big and bright, and the veggies are worthy of blue ribbons. Everything looks absolutely perfect. Just order these seeds and you too can have results like this!

Except, we live in Colorado. There’s a very good reason most seed companies are situated in places like South Carolina, Pennsylvania, and Oregon, where the soil is fertile and the climate is conducive to growing most crops. With our erratic weather, often we don’t have time to ripen those luscious tomatoes. Long-season flowers freeze before they bloom. Isn’t there a seed company for us?

Yes, there is. Appropriately named High Altitude Gardens specializes in short season, cold-hardy varieties that thrive at higher elevations. If you live in the mountains, this is the seed catalog for you!


Bad Daisies

Oxeye_Daisy_TaylorCanyon_2008jul14_LAH_006-001Fresh as a daisy. Daisy chains. “The daisy’s for simplicity and unaffected air.”*

Symbols of simple charm, it’s hard to imagine that daisies could be anything but pure and innocent. Yet, the familiar Oxeye daisy has a dark side. Under that attractive and cheerful guise lurks… a noxious weed!

Take a trip to the mountains to see the wildflowers, and you’re bound to see Oxeye daisies as well. They’re all over the Rockies, preferring the higher elevations. Unfortunately, they don’t belong here. They’re native to Europe, and we heartily wish they had stayed there!