- Jane Shellenberger
August 2024 Newsletter
AUGUST 2024 E-MAGAZINE
Like most people, I've been avoiding the hot sun as much as possible during this very hot summer. But I see a lot of landscape workers and others out there working in it. Derek, the knowledgeable young guy who came to fix our internet set-up, was working up on our roof at noon in 100˚ temps. I read recently that for those of us who say, "I don't do well in the heat", slowly acclimating to it for short periods is probably a healthier adaptive strategy than avoiding it altogether. Makes sense, especially considering the likely long term scenario, though I do feel a bit more optimistic today that we, as a nation, may finally own up to climate change if we manage to elect forward-thinking, reality-based candidates next fall.
Jan Fohs' sunny, unirrigated hellstrip in NW Denver
I made it to two garden tours this summer. First was one of several that featured local rock garden society (RMCNARGS) members’ gardens. We started with Jan Fohs’ unirrigated hellstrip on her corner lot in NW Denver (she confessed that she’d watered a bit for the tour). We saw plenty of tall, reddish-pink Dianthus giganteus, yellow and orange horned poppies (Glaucium acutidentatum), Eriogonum umbellatum 'Kannah Creek', Salvia cyanescens & S. recognita, but her total list for this baking hot strip includes 51 different plants – quite an accomplishment.
It was a pleasure to see some other gardens for the first time that belong to (or were designed by) RMCNARGS members whom I’ve known for years.
Penstemon ambiguus next to the street in Holly Culp's NW Denver garden
At Holly Culp’s garden we happened to arrive at the same time as Panayoti Kelaidis who identified the white, glowing, fairy-like Penstemon ambiguus we were admiring, declaring it the finest specimen he’d ever seen.
My friend Tamara & I ended the day by walking around the Regis University Arboretum, lying down to look up through the enveloping canopy of their mammoth weeping elm and gobbling serviceberries from many heavily bearing Amelanchier trees.
American Weeping Elm at Regis University Arboretum in Denver
A few weeks later, I hijacked my friend Sally from Lyons for a Native Plant Society (CoNPS) garden tour in cooler Estes Park. We began at Mrs Walsh’s Garden, a public gated garden right off the main drag that’s full of Colorado natives, has a pretty little waterfall, and where there was a native plant give-away.
Eventually we made our way to several artful and diverse high altitude private gardens.
Rock outcropping planted with cold-hardy cactus at Jim Conley's garden in Estes Park
One featured cacti of all sorts, another was chock full of interesting rocks from Wyoming as well as plants, and a third was on a 40-acre spread with an incredible view of the peaks. Merle Moore, former Horticulture Director at the Denver Zoo and an early Executive Director of Denver Botanic Gardens, helped organize the tour and also opened his garden. Many of these gardeners went to the trouble of providing detailed plant lists with common and botanical names, and more.
Right now, at the end of July in my own gardens, young grasshoppers burst up into the air like popcorn when I hand water and there are munched holes in lots of leaves. They seem to especially like mint, but that may be just an appetizer. Rabbits are everywhere; they ate almost every bean and pumpkin plant before I covered them with row cover. Red hollyhocks that were 12’ high last year are small shrubs this year and most of the blooms dried up.
Plenty of pie cherries here this year, as well as apricots and apples.
Still, it’s been a pretty good year in the garden overall, though the lack of insects of all kinds except grasshoppers is troubling. Drip irrigation under mulch has made the veggies thrive and we got plenty of cherries, apricots, and mulberries, enough for the birds to share with us.
Yes, I’m watering a lot more than usual. We’ve had almost no rain since April. I keep birdbaths full and I’ve just started filling some feeders in back because the birds must be really hungry. I saw an adult bluejay attack a fledgling – maybe normal jay behavior (?) but I’ve never seen it here before. The Say’s Phoebes (thank you Merlin app) that nested under the front eaves and hung around raising 2 sets of chicks have flown, but still show up once in a while. Those colorful, clownlike Birds-Be-Safe cat collars really do work, preventing the felines from sneaking up on birds, allowing them to focus on their real job – catching rodents.
In this August edition you‘ll find a piece on How to Pick a Plant by John Murgel, Douglas County Extension Specialist, in time for end-of-the-season sales, as well as Lee Recca’s report from the recent Steppe Symposium at Denver Botanic Gardens. Keith Funk answers gardening questions about fall planting, powdery mildew, and watering on these scorching summer days.
Keep cool and calm,
- Jane Shellenberger
Late Season Plant Shopping
How to pick a plant
by John Murgel
Summer is here and most gardeners are working on keeping things growing and happy in the heat. Still, you might find yourself needing one or two more plants for various reasons—a gap in a container, deaths in a garden bed, or perhaps the siren song of the “sale” plants at the garden center.
Whatever the reason, you can help ensure success of new plants late in the season with a few reasonable steps. The first step should be taken before you leave the house--and is a good place to begin any time you’re considering adding plants to the garden. Ask yourself, “What is my goal for this (as yet hypothetical) plant?”
It’s all too easy to fill a cart with plants at the nursery. “I’ll figure out where to plant them later,” we say. But having your objective in mind, along with a timeframe, will narrow your list of potential plants considerably.
For example, suppose you want a plant for privacy screening on the back patio. A new shrub could be just the ticket—except that if the patio needs to be screened ASAP, that shrub may not come through for you in time. You’ll need a shorter term solution to go along with it, or in place of it.
Report from the Steppe Symposium
Rooted in Stone: A Geologist Connects with Gardeners
by Lee Recca Dr. Bob Raynolds kicked off the Global Steppe Symposium by taking us into space to look at the Colorado River Basin and its spectacular geologic features. Then, he brought us down to the garden level to ask us to find solutions and adaptations that will allow people to mitigate climate change, accept climate change, and model new ways of living and gardening.
Raynolds is an eminent geologist with ties to the Colorado School of Mines and the Denver Museum of Nature and Science. His overview of Colorado’s rich geologic history and its rock and mineral layers was dazzling but much of his talk revolved around water. Water not only reveals and interrelates with the mountains, plains and canyons of Colorado but also outlines its most impacted places, carving a series of question marks in its meandering or tumultuous journey to the sea.
Colorado is a unique place in terms of water. It is a “headwaters state” meaning our mountains make the water on which 40 million people depend, including five million Coloradoans. Why is this important to Front Range gardeners? After all, 80 percent of the water in the Colorado River flows west. But Dr. Raynolds pointed out that half of Denver’s water comes from the Colorado River. A majority of that water is used to grow and maintain “green grass,” he said. Green grass in yards, parks, golf courses and other recreational places is not sustainable, he warned. He implored the audience of rock gardeners, teachers and landscape professionals to help people stop living as if they're “in New Jersey.” The “Garden State” boasts 45 inches of average annual rainfall, while Denver averages about 12 inches.
Another area of concern addressed by Dr. Raynolds is agriculture. All of the good efforts of homeowners and gardeners won’t make enough difference, because a whopping 87% of water usage in the state goes to agriculture. Much of that, he said, goes to raising fodder for cattle: alfalfa, corn and hay. His outlook was hopeful that, as people eat less beef, this amount will decrease. His conclusion, seconded by audience remarks, was that it’s not happening fast enough.
Colorado’s Soils and the Plants that Love Them
Whatever you call it – a meadow, a prairie, a clearing, a glade – it’s the space that has recently caught the eye and claimed the heart of many a plantsperson and landscaper. That includes the Denver Botanic Gardens duo of Michael Bone and Kevin Williams.
Building on the opening talk, “Rooted in Stone”, at the Global Steppe Symposium, Williams and Bone sought to “bring the wild home” by detailing which plants, both native and introduced, could thrive in each of the five main ecoregions of the state.
By Keith Funk
Q: What vegetables are good choices for a fall harvest and when should they be planted?
A: Our average first frost date in Denver is typically around October 12 . However, that date can be much earlier or later & is different for other parts of the state. So keep in mind the following suggestions are based on an average year in Denver.
8-9 weeks before frost: Seedlings of broccoli, cabbage, cauliflower, kale; Direct sown seeds of arugula, beets, carrots, chard, kale, lettuces, spinach, peas, radishes
6-7 weeks before frost: Direct sown seeds of arugula, beets, chard, kale, lettuces, radishes, spinach
4-5 weeks before frost: Seedlings of chard, kale; Direct sown seeds of arugula, lettuces, radishes, spinach
Late September & early October: garlic
Many garden centers will be stocking cool season vegetable transplants as the season for planting gets closer. Seed racks have been restocked with fresh vegetable seeds already.
Q: How much should I be watering this time of year?
A: Watering effectively during the heat of summer can be tricky, especially with new plants. My first response is to water deeply and as infrequently as the plants’ health will allow. Use your finger or a moisture meter to determine soil moisture several inches deep. Use a trowel to dig down 6-8” below the surface to see if you are watering deeply enough.
New plants will need to be babied with extra hand watering as needed during hot weather. Don’t rely on lawn sprinklers to adequately water newly planted trees or shrubs.
Gardening Events
Check out our Colorado Gardener Calendar for lots of upcoming events including exhibits, festivals, gardening classes, and presentations. On right: One of the Spirit Guides on exhibit at Denver Botanic Gardens on York St thru Sept 8th.
Do you have events to submit to us? Fill out our form »
