</p> Ranked by CNN last year as one of the seven best places to see holiday lights</a> in the United States, Blossoms of Light</a> offers a spectacular setting for your end-of-year celebrations with colleagues, friends or family.</p> With booking options available every night of the week from Nov. 23 - Dec. 16, we can accommodate parties large and small. Choose from several of our versatile and unique indoor spaces to offer your guests a warm retreat when they aren't outside enjoying our glittering winter wonderland. Party pricing includes a limited quantity of tables and chairs, and each of your guests will have access to wander Blossoms of Light the night of your event. </p> Treat your guests to the most Instagrammable holiday party in town! Popular dates are already selling fast, so contact us for more information today at private.events@botanicgardens.org</a> or 720-865-3551.</p> Thinking of popping the question this December? Ask us about our private engagement packages with a rooftop view of the lights! </em></p>
This summer, Denver Botanic Gardens, with funding from the High Line Canal Conservancy, is conducting a survey of the plants growing along the High Line Canal. Drawing water from the South Platte River, the Canal winds 71 miles from Waterton Canyon in Littleton to the eastern edge of Green Valley Ranch in Aurora. For 66 of those 71 miles, the Canal is accompanied by a multi-use recreational trail, each mile marked by a wooden sign-post displaying the mile number.</p> Those mile markers bear a unique significance to Chrissy Alba, Gardens research associate in floristics, and myself, seasonal botanist, because they mark the beginning of our field work each day. Accompanied by a devoted volunteer or two, we set out from the research van in search of the day’s mile marker, our hand-held GPS leading the way, laden with the tools of the collector: a lightweight plant press, digital camera, field notebooks, clippers and a simple trowel with a unique name, the hori hori. From the mile marker, we slowly work our way downstream, intermittently stopping to collect plant specimens that will be brought back to the Kathryn Kalmbach Herbarium</a> at the Gardens.</p> While searching, we are guided by our species list, which has been compiled over the course of the summer and lists all of the plant species that we have already collected. This list will continue to grow throughout the season; we have already found nearly 200 species in the first six weeks of the project! Our goal each day is to collect plant species that are not on the list, but only if it has flowers or fruits, as these reproductive parts are often critical for identification.</p> When we find a plant in flower or in fruit that isn’t on our list, we must ask ourselves one final question before unholstering the hori hori: are there others like it nearby? If not, we typically won’t collect it, allowing the genetics within that individual to remain part of the ecosystem. Instead, we will make note of it in our field notebooks, adding it to a secondary “observational” species list. The field notebook also contains specific notes for each specimen, including habitat type and other plant species growing nearby. These qualitative data are intended to provide a “snapshot” of the immediate environment in which the plant was found.</p> There are two main categories of plants that we collect on the Canal: those with roots we can collect and those with roots we cannot collect. The roots often provide important information for identification, and for this reason, we want to collect specimens with roots intact whenever possible. Although we’d love to collect the roots of a coyote willow (Salix exigua</em>), for example, it is neither feasible nor necessary. Instead, we use our clippers to collect twigs bearing reproductive parts (flowers or fruits), leaves and any other identifying characteristics, such as thorns.</p> Roots or no roots, all specimens go straight into the field press, a lightweight nylon-and-cardboard version of the traditional heavy wooden frame. The final step is to place a small amount of green leaf tissue from the specimen into a coin envelope, to be preserved for future genetic studies. Plant tissue is needed to address a wide variety of research subjects, ranging, for example, from the drought tolerance of the eastern cottonwood (Populus deltoides</em>) along the Front Range to the genetic makeup of the invasive Dalmatian toadflax (Linaria dalmatica</em>).</p> All told, the process of collecting plant specimens is a pleasantly gratifying, albeit quite slow, process. There is a certain satisfaction that comes to any collector of treasures, no matter what form they might take: each specimen brings you one step closer both to completing the whole picture and to uncovering a new realm of unanswered questions.</p> This blog post was written by Audrey Dignan, seasonal botanist in the Research & Conservation Department.</em></p>
Blotchy patches, serpentine lines, and small black dots inside a clear section of leaf – these are all symptoms I look for when diagnosing leaf miner damage. Leaf miners are the larval form of a few species of flies that live within the upper and lower surfaces on the leaf and feed on the cells inside.</p> Typically, it is nothing more than an aesthetic nightmare. But on plants used for edible greens, like spinach, it develops into a problem that requires management, as leaf miners can decimate a crop, rendering it inedible.</p> The leaf miner flies lay eggs on the underside of the leaf, and once the eggs hatch, bore into the inner space of the leaf. Once inside, they munch on the inner cells, leaving a trail behind filled with small black frass (insect poop) inside the tunnels. After maturing, the flies emerge from the leaves and begin the cycle again. In the fall, the larvae pupate and fall to the soil to overwinter. These insects can have multiple cycles within one year.</p> Depending on the severity of the infestation, there are a number of management techniques available. Spraying insecticides is an option, but the timing is crucial – once the larvae are in the leaf, contact insecticides will not work. Systemic are an option, but have other negative consequences including affecting pollinators and other beneficial insects.</p> The most effective methods of control in a vegetable garden include tilling the soil to disrupt the pupae in the winter, remove the leaves as mines develop and squish the eggs on the undersides of the leaves. Doing a combination of all of these things can prevent a complete decimation of your fresh edible greens. In a perennial bed, however, most opt for either removing the leaves or just ignoring them. </p>
While on one of my scouting tours through the Gardens, Mike Bone, curator of steppe collections and one of the horticulturists that manages the Steppe Garden</a>, informed me that the red hot poker plant (Kniphofia stricta</em></a>,</em> also known as a torch lily) had some interesting fasciation going on in the flower stalks in the Steppe Garden.</p> </p> The torch lily flower stalk is twisting, and some flowers are divided into two. These are some common symptoms of fasciation. Another symptom is a flattened flower, which can be seen in the blanket flowers (Gaillardia aristata</em></a>) in the Ponderosa Border just east of the UMB Bank Amphitheater. Other symptoms of fasciation include a flattened ribbon-like stem, bushy growth or twisted stems.</p> Fasciation is typically a mutation or deformity that occurs in the meristem of a plant. Meristems are where cells begin to form – similar to stem cells in humans, these cells divide and then specialize, becoming the cells that make up the leaves, stems and flowers. Sometimes a mistake happens, resulting in an abnormal growth. These mistakes can be caused by anything from a defect in the DNA code in the plant, to a viral infection, to insect damage. It can even be something environmental that causes this. Because there are so many different causes, there is no one cure.</p> In some plants, like the cockscomb flower (Celsoia cristata</em>), this mutation is transferred by seed, allowing us to enjoy the unique, rooster comb-like flowers year after year. In others, like the torch lily or blanket flower, it is a physiological response, and typically will revert back to “normal” in later flowers or next season. If you’re not keen on how it looks, pruning it out is an option, as this mutation doesn’t generally affect the health of the plant. Otherwise, enjoy the funky flowers and stems!</p>
Water means life everywhere on Earth. But people in semi-arid regions understand this with a clarity born of living in time-step with the rhythmic greening and re-greening of the landscape around them. Anyone who has experienced the sepia-toned end to a Colorado winter has marveled that any flush of life could regenerate from such a hunkered-down thirst. And while our native plants are typically drought-tolerant, the human need of food, fiber, and an inviting shade tree, is less so. To meet these needs, early settlers in many parts of our state tamed the waterways with canals, moving water from mountain to plain, shortening the beat of time during which crops, street trees, and lawns had to go without water. Over time, plants, animals, and people have coalesced along these canals; these ramifying arteries that literally, and in many ways spiritually, sustain life along their banks.</p> The 130-year-old High Line Canal is one such artery, spanning 71 miles from the foothills to the plains, traveling through urban and suburban areas in Denver and the surrounding region. Since 1883, the Canal has been a part of the fabric of the region. The Canal draws water from the South Platte River, beginning at a diversion dam in Waterton Canyon near Littleton and running northeast to Green Valley Ranch. What results is a connective corridor that wends itself through various habitat types, from rugged and wild riparian stretches in the western canyon, to areas reminiscent of native shortgrass prairie in the east. The Canal corridor also passes through many highly developed areas, providing easily accessible green space to thousands of people. A pivotal point in the history of the Canal occurred in the 1970s, when Denver Water opened its maintenance roads, previously patrolled by early “ditch-riders”, to the public. The Canal trail now serves as a recreational hub for walkers, runners, bikers, and horseback riders in the region.</p> From a botanical perspective, the High Line Canal presents an interesting puzzle. Human settlement along the Canal has led to conversion of the surrounding native ecosystems to other land uses. Much of the Canal’s stretch runs through what was historically flat to rolling plains underlain by sandy to silty soils. The grasslands supported native shortgrasses such as blue grama (Bouteloua gracilis</em>) and buffalo grass (Buchloe dactyloides</em>) and a diversity of forbs such as sand lily (Leucocrinum montanum</em>) and scarlet globe mallow (Sphaeralcea coccinea</em>), to name a few. However, increasingly, the Canal’s greenway is surrounded by a built landscape of housing, businesses, and roads. And while there are often pockets of green space that punctuate the built landscape in the form of parks and gardens, these areas may be planted in monocultures (think Kentucky Bluegrass lawns) or contain cultivated plants that are not representative of the region.</p> The question then becomes, what exactly greens this greenway? Botanical staff and volunteers from the Gardens are spending more than 50 field days on the Canal this summer working to answer this question.</strong> (Look for us out on the Canal wearing blue “Researcher” vests, and feel free to stop and ask questions!) We are making plant collections and taking quantitative ecological data on plant communities along the Canal’s entire length from May to September 2018. The Gardens is working on behalf of our funding partner, the High Line Canal Conservancy, which will use the survey data to inform management decisions (see the Conservancy’s website</a> for more information on the Vision Plan for the Canal).</p> So far, our early spring surveys suggest that the flora along the Canal represents a mix of native and non-native plants. For example, it is typical to find native chokecherries (Prunus virginiana</em>), cottonwoods (Populus deltoides</em>), and coyote willow (Salix exigua</em>) mingling with non-native buckthorn (Rhamnus cathartica</em>) or honeysuckle (Lonicera tartarica</em>) along the banks of the canal. There have also been some unexpected native gems, including the uncommon Blue Ridge carrion flower (Smilax lasioneura</em>), which is present in only a few counties in Colorado but was happily growing along the trail in Waterton Canyon! When the data are in, we expect to uncover interesting variation in the make-up of the Canal’s plant communities in relationship to both the west-to-east ecological gradient, and the wild-rural-urban matrix that surrounds the trail. Stay tuned for updates as the field season unfolds!</p> Excerpted and adapted from original publication in Aquilegia</em>, the quarterly publication of the Colorado Native Plant Society.</p>
Purple Mountain sun daisy at City and County Building</p> For over a decade the Master Gardeners of Denver and I maintained a low water garden</a> in front of the City and County Building in the Civic Center of Denver. It was with mixed feelings that I saw this replaced a few years ago with a much simpler, and rather classic garden design. A few days ago, as I drove past, I was startled to see a familiar flash of rosy purple pink: Surely that's not "Purple Mountain Sun Daisy?" I stopped and sure enough, Osteospermum barberiae</em> 'Purple Mountain'--one of the first hardy ice plants to be promoted in U.S. horticulture--was making quite a show. This was introduced to horticulture by Plant Select in 1998</a>--and has gained a steady following across the country over the interim.</p> Closeup of Purple Mountain</p> If you are not familiar with this plant, take a closer look. Photographs have a hard time capturing the distinctive and unique color--somewhere between hot pink and rich purple violet. The color is fantastic, and everyone loves it. There is a slightly darker ring around the disk flowers that make it even more alluring, and it does change hue every so slightly over the days that it opens. The reverse of the ray flowers is a silky bronze color--important because the flowers close at night or in dark weather. And while it blooms most enthusiastically from late April to mid June, there are scattered flowers on this lovely plant all summer long. Did I mention it has leathery, dark green evergreen leaves?</p> Purple Mountain bedded out</p> I take more than a little pride that the park's staff and designers have chosen such a prominent spot to showcase a plant that was debuted at Denver Botanic Gardens in 1991 (a few years later High Country Gardens began to sell this from germplasm they obtained from us). And now I see it popping up here and there around town.</p> Bank planting of Purple Mountain</p> I took this picture of a mass planting at a bank a few blocks from Denver Botanic Gardens a couple years ago--I noticed it's still going strong and blooming spectacularly this year again...</p> I've seen wonderful plantings in Pueblo and Vail--two utterly different environments: the plant obviously has a wide latitude of cultural tolerance. I have friends who have grown it in Massachusetts and California. Truth be said, it does seem sensitive to fungal or bacterial damage in some gardens. If you've had trouble with 'Purple Mountain', do try Osteospermum</em> AVALANCHE (see below).</p> Osteospermum AVALANCHE in the Mordecai Children's Garden</p> If you have never visited the Children's Garden at Denver Botanic Gardens (thinking it was only for kids), do not pass go, do not collect $200 Monopoly dollars--get yourself down there pronto! You will find amazing spreads not only of this gorgeous South African, but of all manner of wonderful montane and alpine plants that thrive in theCildren's Garden's green roof soil mix.</p> Denver Botanic Gardens can be proud indeed to have debuted such an important and uncanny group of perennials. The annual Osteospermums are well and good--but these hardy sorts make plush groundcovers, and bloom for months on end. Perhaps you should include a few in your garden? Who doesn't need a little Purple Mountain majesty above one's fruited plains!</p>
By Colleen Smith, Guest Blogger</strong> Colleen Smith writes and gardens in Denver. She’s the author of </em>Glass Halo and </em>Laid-Back Skier.</p> We humans are no more exempt than the bees and butterflies and hummingbirds when it comes to plants: We’re attracted to their sweetness and beauty. We recognize plants as life. And so we shop. We wander through greenhouses and shuffle through nurseries, searching out plants. We are mesmerized. Hypnotized. Hortiholics. Even if you don’t fancy shopping, but you have the gardener’s genes, you probably enjoy shopping for plants. Shopping for a new swimsuit or a new pair of jeans usually proves depressing. Shopping for a car can require a bank loan and a boatload of anxiety. Shopping for groceries often seems like a necessary but mundane chore. But shopping for plants? A different story altogether. Purchasing plants sets the gardener’s imagination spinning, kicks up horticultural endorphins, benefits the community and the planet. When we support growers, we support growth. Plus, we just might harvest strawberries or love apples, culinary herbs or gorgeous cut flowers for nosegays. Our plants will add fresh oxygen to the air and suck up CO2. The Front Range’s premier plant-shopping extravaganza, Denver Botanic Gardens’ Spring Plant Sale looms on the not-too-distant horizon. Get your tickets for the chic and savvy Preview Party</a> May 8, or mark your calendar for the free admission public sale on May 9 and 10. Find all the details here</a>. Remember to bring your own wagon. Then enjoy the happy state of anticipation because shopping for plants is anything but depressing. Plants help heal us while they heal the world. </p>
Corydalis nobilis</em></p> </p> Fumewort may happen to be the accepted common name, but most of us prefer to call them by their Latin name: Corydalis. Some put the accent on the antipenult, others on the penult: either way--real gardeners will understand! These plants are hot</strong> right now. Dozens are available from specialist nurseries, often at exhoribtant prices. One of the showiest of the bunch, however, has a long history of growing at Denver Botanic Gardens, where several are blooming now. Here is a picture of one in the glory days--they're more modest in size lately!</p> Corydalis nobilis </em>in the wild</p> One of the many high points of a trip I took with Mike Bone five years ago to Kazakhstan at the behest of Plant Select was finally finding this familiar plant in the wild! Although we covered many miles in the Altai mountains both in Kazakhstan and Mongolia, we only found this one patch of the Corydalis</em> growing on a north facing talus slope not far south of the Austrian Road summit.</p> Corydalis nobilis</em></p> Here is that colony a little closer up.</p> Corydalis nobilis</em></p> And here you can get a better picture of a whole plant up close. There is something unique about the bearing of this plant . . . the graceful bluish fernlike tuft of leaves, and those clusters of bright yellow flowers with the darker spot in the center! People find this irresistible--whenever they find one at the Gardens they always comment on it.</p> Brunnera macrophylla</em></p> You can imagine my surprise when Tom Van Zandt, a member of the Gardens in Boulder, called me to tell me that his neighbor had dozens of Corydalis nobilis</em> naturalized in his garden! THIS I had to see...I drove up to Boulder yesterday, and was a little taken aback to visit the old Rockmount Nursery site I knew well as a child growing up in Boulder, chockablock full of Siberian forget-me-not (Brunnera macrophylla</em>). This last undeveloped corner of this famous nursery was purchased from Darwin Andrews, and the current resident has maintaned the site--removing weeds and allowing the plants there to coast on, entirely on whatever moisture comes out of the sky. There are some famous trees--state champions--growing here that I've visited in the summer: a giant Post Oak (Quercus stellata</em>) and an even more imposing Shingle Oak (Quercus imbricaria</em>). But I didn't expect to see literally millions of Siberian squill (Scilla sibirica</em>) which unfortunately had just passed over bloom. And large Peking lilacs (Syringa reticulata</em>) and many other exotics that had persisted with little care and no water for decades. Did I mention there were masses of Colchicums</em> in leaf--likewise naturalized, and several husky clumps of herbaceous clematis (Clematis integrifolia</em>) in the grassy opening between the woods. By the way, if you look in the back of this picture you will see some pale yellow glimmerings...</p> </p> Yes! Here is the first Corydalis nobilis</em>, in gorgeous combination with the forget-me-not: a combo any designer would pride themselves on!</p> </p> Everywhere I looked there were masses of Corydalis</em>, growing with amazing vigor!</p> Corydalis </em></p> The site was a rocky slope, not unlike where I'd seen them five years ago in Kazakhstan, albeit nearly two months earlier in the year.</p> </p> The owner of the home has approved of our obtaining seed from these colonies. It's highly unlikely you will find this corydalis</em> at our plant sale this year, or anywhere mail order I know about for that matter. But we shall make an effort to grow as many as possible. I can't wait to re-create this combination of corydalis</em> and forget-me-not at my home!</p> Notice the corydalis</em> in this last picture is coming up through English Ivy, likewise naturalized here! Boulder does get a few more inches of precipitation than any other city in the state below 6000'--although Boulder has had its share of drought years. Seeing all these plants persisting in cultivation after decades of benign neglect brings up the spectre of "invasiveness." I suppose the Brunnera</em> is growing so widely and thickly one would be cautious about planting this? I have grown Brunnera</em> many times--and it will indeed produce lots of seedlings in the garden, which I find pretty easy to remove. I think it's a question of finding a spot where you don't mind having them spread. There were many dozens of Corydalis</em> throughout the woods, it's true, but they have probably been growing at that site for half a century at least--probably more like a century. This is growing in dozens of garden I know of in the Front Range, and I have never heard anyone complain about its producing too many seedlings (there are always takers!).</p> What this really brings up for me is a major solution to the perennial question: "What do I grow in dry shade?": This is probably the most frequently asked question I've had over the decades. I can now respond enthusiastically: plant Siberian squill, Colchicums</em>, siberian forget-me-not and Corydalis nobilis!</em> And it is very possible that in a hundred years, you will have botanic gardeners like me marvelling at your low maintenance, xeric garden! Thank you, Tom, for showing me one of the great horticultural wonders of Colorado!</p> </p> </p>
</p> The "Green Roof" or eco roof concept has become a billion dollar industry in Europe, where storm water abatement and water quality are top drawer concerns. With the catastrophic flooding of last September fresh in our minds, we in Colorado should rachet up our concern. We are lucky to have a horticulturist coming to Denver Botanic Gardens to speak who has had extensive experience with eco-gardening at the University of Pretoria in South Africa.</p> Jason Sampson</p> April 19 from 1-4 p.m. at John C. Mitchell Hall, Denver Botanic Gardens</a> Jason Sampson, Curator, Manie van der Schijff Botanical Garden at University of Pretoria, will be talking about "Green Walls" (1 p.m.) and "Hybridizing Aloes" (2:30 p.m.). Please email me at kelaidip@botanicgardens.org</a> if you can attend either lecture so I can put you on the class list.</p>
