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Mikl's Articles

Winter Solstice 2020

This year the Winter Solstice will fall on Monday, Dec. 21st

This astronomical event is the time when the Earth’s north pole is tilted farthest from the sun, so that here in the northern hemisphere, night is the longest and daylight is the shortest. This day has long been celebrated because it signals the reversal of the trend, with days lengthening until Summer Solstice. So even though there is a lot of winter left, there will be more day light. It is the promise of rebirth, of Spring to come.

Peoples through different times and cultures have seen this event as a moment of rebirth and hope. [Read More]

Mother Nature’s Dryland Natives

On our hikes, it seems we’re often exclaiming, “What a beautiful plant combination!”.  Mother Nature’s inherent beauty and functional placement provide an amazing guide and inspiration for what we can create in our home garden or ecosystem. Mother Nature also helps guide us on how we can best support our pollinators.

In the new Harvest 2020 issue of Colorado Gardener (with a striking mushroom cover photo!), Mikl writes in ‘Blooming Without a Care’ about a selection of wonderful lesser-known dryland native wildflowers that can also be very successful garden plants in our semi-arid climate. [Read More]

MANAGING WEEDS WITHOUT POISONS by Mikl Brawner

Some people repeat Ralph W. Emerson, saying “A weed is a plant whose virtues remain undiscovered.” But although I appreciate that many weeds do have virtues, I doubt that many gardeners would accept that definition as the final word. Most of us have had extensive experience with Bindweed, Thistle, Goathead, Ragweed, Dandelion and Cheat Grass; not to mention some aggressive natives like Whiplash Daisy, Wood’s Rose and Hairy Goldenaster; and certain herbs like mints, Comfrey and Sweet Grass. So in talking about managing weeds non-toxically, the main point seems to be: How can we keep certain plants under control?[Read More]

BUILDING TOPSOIL AND SOIL FERTILITY by Mikl Brawner

“Where can I get some good topsoil?” That’s a question I hear frequently at our nursery. And I often look wistfully towards the plains and say, only half-jokingly, “You can get good topsoil about 800 miles east of here.” That’s where I grew up, in Iowa, and where two tomato plants feed a family of six. It’s not that local suppliers are trying to deceive us when they sell Colorado clay as topsoil; it’s just that the glaciers didn’t dump three feet of loam on top of our clay.[Read More]

The History of Harlequin’s Gardens

In October of 2018, we were asked by the Rocky Mt. Chapter of the Rock Garden Society to give a program that would include a history of Harlequin’s Gardens. Mikl has been a member of that excellent organization since the mid-1980s and so he composed and presented this playful and humorous account of the evolution of our nursery. We think you will enjoy it!

 

A Not-so-BRIEF HISTORY OF HARLEQUIN’S GARDENS

Harlequin’s Gardens has just completed our 26th year in business. It’s practically a miracle. We were able to get our start and have survived this long because of some remarkable circumstances, some remarkable people, a genuine vision, strong determination, and just plain luck.

In the beginning, my ignorance kept me from knowing the depth of the hole I was digging myself into. I had no idea of how complex and all-consuming the nursery business can be. But it wasn’t all ignorance; I was smart too. Early on, I joined the Rock Garden Society, and later I married Eve Reshetnik. But I’m getting ahead of the story. [Read More]

Lycium (Goji Berry)

Whoever heard of Goji Berry 20 years ago? Now, with the current interest in superfoods, phytonutrients and antioxidants, Goji Berry juice and dried fruits can be found in many urban grocery stores. The 70+ species of Lycium are found on most continents and one species, Lycium pallidum, is native to Colorado. But the best known and most grown Goji is Lycium barbarum, the Chinese Wolfberry, also known as Matrimony Vine, Desert Thorn and Boxthorn. What is not commonly known is that this exotic superfood can be easily grown in Colorado.[Read More]

Insectary Plants: Let Nature Manage the Pests

It’s a common idea that Nature, left to its own devices, comes to some kind of balance. If one organism gets too numerous, something else will increase to reduce that population. In the case of monocultures created by humans, there is an enforced imbalance that has to be propped up with lots of energy and effort. So in the pursuit of sustainability, humans are opening our eyes to the possibility of biomimicry, imitating Nature. We are coming to the realization that biodiversity is far healthier and less energy intensive than monocultures born out of the aggressive hubris to control Nature. “Let Nature take her course.” But we can stack the deck in human favor first.[Read More]

Biological Farming & Gardening

A newer science that’s not tied to petroleum profits is emerging to challenge the industrial approach to agriculture and gardening. Enormously powerful, politically connected giants like Monsanto, Bayer, and Dupont will continue to make money, but after 60 years of dominance, the “Better Living Through Chemistry” model can no longer hide its fatal flaws. Mountains of evidence now point to the downside of chemical agriculture: poisoning the earth, driving global climate change, causing major health problems, killing pollinators, destroying the life of the soil. The good news is that a more long-range, wholistic view called Biological Agriculture and Gardening is starting to take its place.

This “new” method is based on an entirely different paradigm or model of plant culture. Instead of the bellicose mentality that birthed the pesticide-fungicide-herbicide and chemical fertilizer approach, the biological approach taps the same cooperative relationships that Nature herself has long employed successfully for survival and sustainability. Instead of seeing bacteria as germs, fungi as diseases, and insects and weeds as pests, the biological model sees Nature as brilliantly creative and diverse, and basically good. The scientific truth is that few insects, bacteria and fungi are harmful; most are beneficial or essential to plant development, plant health, and subsequently for human health.[Read More]

Curl-Leaf Mt. Mahogany

Curl-leaf Mt. Mahogany (Cercocarpus ledifolius)

This tall shrub or short tree is a beautiful broadleaf evergreen that is native to Colorado and much of the west up to 9000’. It’s narrow, curled leaves are an adaptation to reduce exposure to drying sun and wind; consequently it is very drought resistant, needing no irrigation after being established.The leaves are also thick, leathery, resinous and dark green above and pale below. Flowers are mostly inconspicuous and the fruit is only 1/4” long with a 2”-3” long silky tail. In dry weather these tails twist like a cork screw and with a little wind can be carried a good distance and then they will screw the seed right into the soil.[Read More]

2011 Plant Select Winners

Plant Select is a 25 year old cooperative program combining the efforts of Denver Botanic Garden, Colorado State University and some members of the local green industry. Their intention is to chose, propagate and promote plants that are well-adapted to Colorado conditions, colorful and are either little known or underutilized. The 2011 choices are a particularly excellent group.[Read More]

Xeriscape Herb Garden

Usually when we talk about xeriscape gardening, we think of rock garden kinds of plants or natives, but there are a lot of herbs that survive and even thrive in low water conditions. I learned about this from my own herb garden which went from low water irrigation to next to no watering. It had been established for ten years and then three years ago, I had to cut back the watering to only a couple times a year.[Read More]

Cherry Trees on the Front Range

According to some reports, Colorado weather in 2014-2015 has resulted in the deaths of 80% of our cherry, plum and peach trees. How did this happen? Does it make sense to replant? And if so, how can we reduce future losses and increase fruitful successes? This article will focus on cherry trees.[Read More]

A Xeriscape Harvest

For most people, harvest time brings to mind a cornucopia of veggies and fruits. For me, the end of this 2009 growing season has been a fruition of over 20 years of cultivating a xeriscape where most of the trees and shrubs have been watered 5 times a year or less. These self-imposed watering restrictions have demonstrated which plants can survive and thrive under serious water shortages. I have done this both to encourage water conservation in Colorado and to demonstrate that a dry western landscape can be beautiful.

The reason why 2009 feels like a harvest year is because many of my woody plants are now mature and because with all the rain we’ve been getting, my xeriscape has never looked better at the end of summer.[Read More]

Big, Bold, and Beautiful

If you’ve got room for some big splashes of color in a garden that is not pampered with water and fertilizers, here are some tough natives that will pay for their real estate.

Desert Four O’Clock, Mirabilis multiflora is a Colorado perennial that, like its annual cousins, blooms from late afternoon to mid-morning. The trumpet-shaped flowers are of a rich purplish rose color and virtually cover the foliage when the flowers are open, blooming for several months starting in July. The leaves are thick and blue-green. They look so innocent as seedlings, and then they grow and grow to a 3’-4’ mound, 1 ½-2’ high. The stems lie on the ground, providing a mulching effect.[Read More]

Growing Roses Without Chemicals

Here is the basic approach which we use at Harlequin’s Gardens to grow hundreds of roses without using any pesticides or fungicides, and only using a few soft controls.[Read More]

A Soil Revolution

In this article, Mikl explains why Soil Health matters.

From Peak Soil to Soil Revolution

We are having a real revolution in our relationship with our soils. The turning point is our change in focus from soil fertility to soil health. In the last 60 years of the “Green Revolution” (i.e. the petrochemical boom), soil was viewed as a physical structure and fertility was viewed as a measure of chemicals in the soil — primarily NPK, nitrogen, phosphorus and potassium. The petroleum industry could make these macronutrients from natural gas, which make plants grow but often in poor health. Weak plants attract insect pests and fungal diseases, so more petroleum in the forms of insecticides and fungicides added to the success of the oil industry. But this approach has led to “Peak Soil” where land is losing productivity, crops are losing nutritional value, the soil is eroding at extreme rates, and the health of animals and people has declined.[Read More]

How Do We Manage Fireblight

Colorado is said to be the worst state in the US for fireblight, and 2018 was considered by many to be one of the worst years in Colorado. Fireblight is a serious disease affecting apples, crabapples, pears, Mountain Ash and hawthorn, and sometimes quince and pyracantha (supposedly up to 73 species of plants).[Read More]

Growing Agave in Colorado

Most of us in Colorado know that Agave is the source of tequilla and Agave sweetener, but fewer have seen it growing here. Even more rare is the sight of Agave in bloom. The Century Plant doesn’t really take 100 years to bloom, but it does seem to take forever. After 13 years, my Agave parryi, whose bold and armed rosette finally achieved 31” in diameter and 16” tall, began this May to push up a bloom stalk. Then it skyrocketed 3”-4” A DAY until it reached eleven and half feet tall with a candelabra  of rich yellow flowers. Eclectic horticulturist Bob Nold says in his book High and Dry, “Their flowering, mostly, is as spectacular a thing as the plant kingdom has invented….”[Read More]

Drought Resiliency

Drought resiliency is normally thought of as the ability to spring back after a drought or maybe it means tolerant of drought. But when a plant is stressed by having little water, its ability to survive and even thrive is influenced by other factors, some of which are Health, Vitality, Strength and Immune function.

The word Sustainability has become popular as a goal, but the word is too static. A more active word is Re-generative. We can “create” gardens that not only can maintain, but also support the abilities of Life to regrow, multiply, defend itself against predators and add to the vitality of other living things around it.[Read More]

Drought Water Restrictions

Drought, Water Restrictions and Gardening: How Can They Go Together?

I think we were all caught off guard by this drought, by how fast we were forced to see dying trees and brown lawns and by the difficult discipline of watering restrictions. This was especially true in Boulder and Lafayette where mandatory restrictions began in May. Actually, 2002 is the third year in a genuine drought, which some of us without city water supplies can confirm. This year all around Boulder, Red Twig Dogwoods turned brown, linden leaves were scorched, Norway Maples suffered, many viburnums were looking very stressed, and trees in medians defoliated or died. Gardeners caught in the crunch between weeks of hot, dry weather and few opportunities to water, held off most of their planting projects; some started talking about moving away to where they could garden. For Denver and other Colorado cities, next year could be much worse.[Read More]

July Color in the Xeriscape Garden

Xeriscape? Are you kidding? With all the rain we’ve been getting, isn’t the drought over?

As I understand our current water situation, water restrictions are still in effect for the Denver area, Colorado Springs has had a very dry spring until July and is under water restrictions, the Western Slope has been dry, New Mexico has been dry until July; and  Montana and South Dakota are having severe droughts. What this means is that the wonderful moist season we are enjoying in the Denver area depends on ephemeral conditions we cannot count on. In addition, much of our water comes from the Western Slope where weather patterns can be quite different from our own, so even if our gardens are getting watered, it doesn’t mean our reservoirs will be full. We live in a semi-arid environment and water conservation and xeriscaping will be increasingly important as our population grows, especially if global warming increases our temperatures.[Read More]

On The Dry Side

Plants that can survive and even thrive with little water are always valuable in Colorado where we get 15”-18” of precipitation most years. But when a real drought comes or when limited snowfall in the mountains means water restrictions down here, then xeriscape plants are essential in our gardens

Because the well at Harlequin’s Gardens nursery is so poor, my rockery garden has been on water restrictions for the last 25 years. Here are some plants that have performed well in my garden that is watered only 3 to 7 times a year.[Read More]

Opportunities and Tricks of Xeriscape

Since the drought of 2002, there has been some real progress in understanding and appreciating xeriscape or water wise landscaping. And yet some people think the drought is over and that we can go back to assuming that we have as much water as we want. But it is quite possible that we could have more droughts, and it would be painful to be as unprepared as we were in 2002. That was our wake-up call. And even with the moister weather in recent years, peoples values are changing. They are more interested in sustainable landscapes, and they want more economical landscapes and gardens that need less water, time, energy and money. And of course that means using plants and methods that are adapted to Colorado conditions.[Read More]

Some Drought-Tolerant Gems

Plants that tolerate or even revel in hot, dry conditions are always in vogue in Colorado. We may be blessed with moisture in the spring, as we had this year, but by June or July our vegetables need regular watering and east coast woodland plants are melting. There are some plants, however that are adapted to hot and dry conditions. Some are natives and some are from other regions of the world that have similar drought stresses as we have here.

These gems are ones that we have tested at Harlequin’s Gardens where none of our demonstration gardens are watered more than once a week, and others only 5 or 6 times a year. We can recommend these plants as successful and enjoyable under mandated or self-imposed watering restrictions.[Read More]

Testing Xeriscape Groundcovers

TESTING XERISCAPE GROUNDCOVERS TO REPLACE LAWN AREAS

Whether this turns out to be a drought year or not, the idea of conserving water is probably as vital to our future as educating our children. As long as the human population grows, the demand on our water reserves will continue to rise, forcing eventual water-rationing even if the supply stays the same. And as we have seen this year, we can’t count on a bountiful supply from the heavens. Ten years ago these ideas, and the fact that my own water source is a very low-producing well, got me to thinking about how much water we use in Colorado to water our lawns. We know that xeriscape plants use less water than bluegrass, so why couldn’t we use large areas of certain low-water plants to replace lawn, which could greatly reduce the demand on our valuable water? In order to test a variety of xeriscape plants that might function as replacements for Kentucky Bluegrass, I built a 104′ x 6′ demonstration garden which will be on the 2002 Xeriscape Garden Tour, taking place in Boulder June 29th and 30th.[Read More]

The 2002 Drought

Drought, Water Restrictions and Gardening: How Can They Go Together?

I think we were all caught off guard by this drought, by how fast we were forced to see dying trees and brown lawns and by the difficult discipline of watering restrictions. This was especially true in Boulder and Lafayette where mandatory restrictions began in May. Actually, 2002 is the third year in a genuine drought, which some of us without city water supplies can confirm. This year all around Boulder, Red Twig Dogwoods turned brown, linden leaves were scorched, Norway Maples suffered, many viburnums were looking very stressed, and trees in medians defoliated or died. Gardeners caught in the crunch between weeks of hot, dry weather and few opportunities to water, held off most of their planting projects; some started talking about moving away to where they could garden. For Denver and other Colorado cities, next year could be much worse.[Read More]

Three Xeric Plant Select Favorites

Here are three hardy, xeric and floriferous plants that are successful in western gardens.

Russian Hawthorn, Crataegus ambiguus was tested at the Cheyenne Horticultural Station and found to be well-adapted to the west. It is native to Armenia, Iran, Russia, Ukraine and Turkey. I have a 20 year-old specimen growing without irrigation along with many native shrubs. The mature size is 15′-20′ high and wide in our area. The branches grow quite horizontally which gives it natural character. It lends itself to a bonsai/character style, and I have been growing one in a big ceramic pot for 10 years. The finely cut leaves give a soft appearance and in May it blooms with profuse white flowers that are attractive to bees and butterflies and followed by showy red berries in August/September that are eaten by birds. Very dry conditions can result in fewer flowers and fruit. Like apples, to which Hawthorns are related, the seeds contain some cyanide, so should not be eaten, but the berries are edible and make a respected heart tonic.[Read More]

Xeriscape Perennials That Withstand Colorado

“The quality of mercy is not strained
 It droppeth as the gentle rain from heaven.” Shakespeare

It was great to have a long cool spring with plenty of moisture, but since it followed the very hot temperatures and drought of 2002, it really felt like a merciful blessing. Now instead of dying trees and brown lawns, the streams are gushing, the reservoirs brimming, the wildflowers are extravagant and the birds are joyfully singing. Those plants and gardens that survived 2002 have never looked better. We’ll take it.[Read More]

Beyond GMOs and Petroleum Farming

Four years ago I was among the group of Boulder County residents who were asking to ban GMOs on our publically-owned farm lands. The Commissioners at that time voted to add GMO Sugar Beets to the already approved GMO corn, but they also increased the acreage of land to be used for organic agriculture and agreed to take another look at neonicotinoid use if there was new evidence. There is now new evidence on GMOs, Roundup that is used on 80% of GMOs and on neonicotinoids linked to the death and weakening of all our insects, including bees.

So in 2011, in order to find out if there were practical non-toxic options to manage larger pieces of farm land (like 200-300 acres), I traveled to Ohio to an Acres USA Conference. Attending that conference were over a thousand farmers and ranchers. ACRES has been guiding eco-agriculture for 45 years now; the last conference I had attended was in 1977. I met farmers and attended talks by farmers who were managing 100-1000 acres without GMOs and without toxic chemicals.[Read More]

The Drought Response

Responding to the worst drought in 100 (300?) years has been confusing, disturbing and difficult. The main unanswerable questions are, “How long is it going to last?” and “Is global warming or other conditions going to cause this kind of drought to be more common place?” Implicit in these questions is the question being asked by water utilities, city governments and members of the Green Industry: “How much money should we invest in changes that will conserve water?” If in two years the drought is over and will not be this bad again for 100 years, then why bother to reinvent our utilities and businesses? On the other hand, if water providers, city councils and the Green Industry are not proactive about water conservation, and the drought cycle lasts for a long time, consequences could be devastating, and the public could get furious.[Read More]

Quaking Aspens

Leave them to the Mountains OR Plant them at Home?

Populus tremuloides or Quaking Aspen is not only one of the best-known native trees here in Colorado, but it is said to be the most widely distributed tree of North America. Its narrow, roughly pyramidal form is commonly 25’-30’ tall and 15’-20’ wide, although it can get much larger. The leaves are shiny, dark green above and light gray-green beneath which makes the tree shimmer in the breezes. Also its whitish trunk adds to its attractive architecture. Then in the fall the leaves can turn a rich golden yellow which look glorious on the tree and lovely on the ground. It has a suckering habit which inclines it to clumps and which has put aspen in the running for the world’s largest being.[Read More]

Bigtooth Maple

Bigtooth Maple, Acer grandidentatum, is native to the far southwest corner of Colorado in a place known as Sleeping Ute Mountain. It is common in canyons, northfacing slopes and along mountain streams in Utah, Wyoming and west Texas from 5000′ to 8000′. Although most often listed as a separate species, Bigtooth Maple is sometimes called Western Sugar Maple, therefore, a subspecies of Acer saccharum. Its other names are Canyon Maple and Wasatch Maple.[Read More]

Bur Oak

BUR OAK—QUERCUS MACROCARPA-MOSSY CUP OAK

One of the most successful oaks for Colorado is the Bur Oak. It is adaptable to our clay soils and tolerates our alkaline conditions better than most oaks. In harsh, droughty areas this tree can be a low shrub, but on rich, river-bottom land can get 170’ high and 6’-7’ in diameter; but most often grows 50’-70’ high. The trunk is often thick and short with deeply furrowed bark, and the stout branches often extend almost straight out making the tree as broad as tall. The leaves are deeply lobed only in the bottom half and these lobes are rounded not pointed as with many other oaks. The acorns are distinctive in that there is a mossy fringe around the cap. The overall effect can be quite grand and sculptural, sometimes like a Chinese painting. The short taproot is surrounded by a massive root system which is strongly competitive. This is why old specimens often are standing alone.[Read More]

Catalpa

Western (Northern) Catalpa- Catalpa speciosa

It is surprising that a tree that looks so different from the other Colorado-adapted trees, is so successful. What stands out immediately are the huge leaves which can be 3”x 6” or even 6” x “12” and are heart-shaped. And in June, this large shade tree blooms exquisite, ruffled, bell-like, white, fragrant flowers with yellow and purplish coloration .And in the fall the passerby might be surprised to see the long thin pods 10”- 18” long.[Read More]

Champion Trees Show More Possibilities

Growing trees in Colorado, especially big shade trees, can be very challenging. Few of the specimens in our community “forests” are native to Colorado, and areas where big trees are abundant are often so different from our conditions that those trees do not adapt well here. Some of the difficulties trees face here are: alkaline soils, nutrient-poor and shallow soils, low humidity, hot and drying winter sun, strong winds, untimely wet snows in spring and fall, rapidly changing temperatures, and low rainfall. Add to these the confining root zones in which many trees are growing in urban environments, and it is easy to understand why our trees are often stressed, subject to borer and fungus problems, broken and short-lived.[Read More]

Why Plant A Once Blooming Rose?

I know of one lilac that has some repeat flowering in the fall, but I’m not aware of any spireas, mockoranges, shrub honeysuckles, forsythias, serviceberries, butterfly bushes, rabbitbrushes, cotoneasters, or other shrubs that repeat their flowering cycle. Why is it, then, that many gardeners demand continuous flowering roses ? We want them, of course, because they exist.

The fixation on constant flowering is encouraged with annuals, which, of course, don’t really start blooming until late spring or summer and then the first winter, they die. And seasoned gardeners know that the search for perennials that “bloom all season” leads to the proper selection of many species that will bloom in succession. So when we hear of roses that bloom from May or June through September, we think we have found the holy grail. However there are qualities besides repeat flowering which could entice us to cultivate the so-called “once-blooming” roses. I would like to share these not-so-obvious reasons with you.[Read More]

Kentucky Coffee Tree – Gymnocladus dioica

This member of the pea family (Fabaceae) can get 50’-60’ high and 30’-40’ wide, though most that I’ve seen in Colorado are under 45’. Nearly everybody thinks of this tree as interesting or picturesque.The branching is more open than most trees and the bark is gray to dark brown, rough and deeply ridged even on small branches. The leaves are  bluish-green and somewhat tropical-looking being double compound, each one 18”-24” long and forked with small leaflets alternating on the stem. Fall color is yellow. As the species name implies, this tree is dioecious, having the male and female flowers on separate trees. The flowers are greenish-white, supposedly fragrant and not conspicuous. On the female trees, tough, leathery seed pods follow that are 4”-6” long and 1 1/4”-2” wide. These hang on after the leaves fall and into the winter.[Read More]

Hackberry

Common Hackberry  (Celtis occidentalis)

Why would anybody be interested in a tree that is just the common variety? In this case, we Coloradoans can be very interested because “common” means it will grow just about anywhere. In our harsh country that provides a good living for people planting and replanting and pruning and re-pruning trees, the Common Hackberry is somewhat of a relief. It will grow to 7000’. Our 25 below zero winters do not bother it as it is hardy to zone 2, which helps a lot in adjusting to our sudden warm-to-cold swings. It is also not picky about soils, tolerating both acidic and our usual alkaline conditions; rocky is fine, heavy clay is OK; it really likes rich, moist, but grows right along in poor, dry, windy, polluted cities. [Read More]

How to Plant a Tree

Planting a tree puts us in touch with one of the most essential parts of a tree that is often overlooked—the roots. When a seed germinates, the first part to develop is the root. The seed has stored nutrients, but if the plant is to live, it must immediately make a relationship with the nourishment of the earth. Then it can make the sprout that pushes into the sunlight to start photosynthesizing. So the first matter of importance in planting a tree is to honor its roots—their condition, their future environment and their nourishment.[Read More]

Sustainable Roses for Colorado

Tea House Roses, photo by Nikki Hayden

Roses are certainly one of the world’s most beloved flowers, and yet many people have given up on them because they have gotten the reputation of needing frequent spraying, feeding and fussing. They got this reputation because for decades, hybrid tea and floribunda roses were bred mostly for special colors, a particular flower form and repeat flowering. Their value was judged more for the exhibition table than for the garden. Now, as more people have become aware of the dangers of pesticides and as the trend has moved to “care-free” shrub roses for the garden, rose breeding has shifted in the last ten years towards more sustainability.[Read More]

Mountain Ash

European Mt. Ash (Sorbus aucuparia)

This is surely one of my favorite ornamental trees for the front range which can be used up to 8000’.It is an upright oval tree spreading with age 25’-30’ tall aned 15’-25’ wide. If cared for, it will be attractive throughout the season. The bark is a shiny, orangy-brown. The serrated, compound leaves are dark green and in the fall turn yellow and reddish-gold. The clusters of flowers are white, blooming in spring with a peculiar fragrance that some people appreciate more when they’re gone. Clusters of red-orange berry-like fruit follow which color the tree through the fall, accenting the orangy leaf colors. These fruits are greatly loved by the birds and are in fact edible for people. They are known as Rowan berries and are used in Europe in making a brandy. In ancient times the Rowan tree, also know as the Quickbeam, was greatly revered by the Druids and used against lightning and witches’charms. The berries were considered extremely valuable having the “sustaining value of nine meals”, healing the wounded and giving a man the strength of ten men. I had to try this, of course, and found I couldn’t eat even 10 berries. Later I learned they need to “blet” or shelf-ripened. The birds do spread these around, and Mt. Ash seedlings are not uncommon.[Read More]

Pinyon Pine – Pinus edulis (Pinus cembroides edulis)

The Pinyon Pine has several advantages over other evergreen trees in a Colorado landscape. For one thing, its size doesn’t consume so much horizontal space. Compare the modest mature Pinyon at 10’-15’ in diameter with Austrian or Ponderosa at 25’-35’ diameter or Blue Spruce at 30’-40’ diameter. A few of these “average” sized evergreens look innocent when freshly planted, but who hasn’t seen them blocking sidewalks and doorways, tearing off gutters and shading solar collectors and windows in the winter? The Pinyon with its gently rounded top only gets 12’-20’ high, which suffices for many screening needs and still leaves the view. If it isn’t crowded, it stays branched to the ground with dense foliage of short, medium green to gray-green needles, two to a bundle. The cones are small 1 1/2”-2” long, brown to reddish-brown, which open to a rosette form and in the wild yield Pinyon “nuts”. These seeds are good-tasting and oily, with a piney flavor much appreciated by birds, animals and humans. They are also nutritious, being higher in protein and carbohydrates than pecans, but lower in fat. For some reason , these “nuts” are unlikely to develop in small urban plantings.[Read More]

Redbud

One of the most beautiful ornamental trees is the Eastern Redbud, Cercis canadensis. It is a native of the eastern and southern U.S. and has “naturalized” in older Boulder neighborhoods. It’s most distinctive feature is its reddish purple buds  followed by intense purplish-pink pea-like flowers in late April before the leaves come out. This wondrous and heart-warming display is greatly appreciated so early in spring but cannot be counted on if winters are too harsh.

It is a smaller tree 20’-25’ high and wide with attractive bark and heart-shaped leaves which are shiny and purplish when young. Fall color is yellow. It is said to be hardy  to zone 4 and we have many fine specimens in Boulder.[Read More]

Small Trees for Eastern or Northern Exposures

Shade trees 40’-60’ high and wide are great on the south and west sides of our houses and offices. They reduce temperatures and reduce cooling costs in the warm months, but they are not always appropriate. We don’t want dense shade where we grow most xeriscapes, rock gardens, herb gardens, most natives and many perennials. In addition, there is no need for big shade trees on the north side, and the morning sun is usually welcome on the east side of our houses and workplaces. And many plants prosper in morning sun and afternoon shade. It is also significant that a 20’ tree costs far less to have pruned than a 40’ tree. So it seems to me we should be growing small trees under 30’ tall on the east and north sides of our buildings.[Read More]

Stressed Trees: How to prune and care for them

Trees have it hard in Colorado. If it’s not the shallow and lean topsoil, it’s the low rainfall and low humidity, or it’s the heavy wet late spring or early fall snows, or like last November, it’s the dramatic temperature changes. After a warm and beautiful fall without a killing frost until November 11, we experienced a 77 degree drop in temperature between November 10 and November 12. This was one of the three largest temperature drops ever recorded in the Denver area, the other two were in December 2013 and January 2014.[Read More]

Supporting Trees in Colorado

Trees do a lot for us humans, so we shouldn’t forget to give them some support. When I look at the treeless ten acre lot next to our nursery, or when I see an old photo of the CU campus with bare land around Old Main, I remember why we can’t take trees for granted in Colorado. Trees really have it hard here, but there are things we can do to help them survive and thrive.[Read More]

The Pruning and Care of Young Trees

Of all our plants, trees take the longest to develop and so it is not only heart-breaking, but a significant set-back to a landscape when a tree that is 10-20 years old is destroyed in a storm. Many of these disasters could be prevented with proper pruning early in a tree’s life. Besides preventing disasters, pruning trees properly when young will help them to develop more beautifully, make them stronger, less expensive to maintain as they get older and keep them healthier.

A young tree, like any young being, is vulnerable and needs some extra care. And trees are often a costly investment, both for the plant and for the planting. So since few arborists will come out for the fifteen minute job of pruning a young tree, and since few lawn crews are trained in proper pruning, it is good for home-owners to understand the basics of pruning in order to get their trees off to a good start.[Read More]

Tree Roots 1: The hidden support system

The roots are the hidden support system of our giant plants, the trees. They anchor their woody trunks to the ground, store food and bring in water, nutrients and oxygen. In this article I will discuss what is going on down there. In the next issue I will discuss more practical applications of this understanding.  

Far less is known about tree roots than about the trunk, branches and leaves. This is understandable since the roots are hidden from our view, and once you dig them up, they are no longer what they were. We are awed by the massive trees swaying over our houses and streets, but usually we give little thought to what is going on under the surface. However, when spring thawing is followed by powerful winds and we see an 80’ spruce toppled over with its roots in the air, which are only 9” deep; that gets us thinking.[Read More]

Tree Roots 2: The hidden support system part II

What would we do without trees? What structures could we invent and construct that would hang over our houses and offices, providing shade and cooler temperatures? Such a structure would have to hold up under 80 mph winds and heavy wet snows, and would have to retract in the winter to let in light. Trees provide these values and much more, giving off oxygen, providing housing for birds, and protection for understory plants. Thus it is very important to take good care of our trees, and the most fundamental level of that care must be directed to the roots.[Read More]