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Allan designs and plants flowering gardens in Montreal, Zone 5 [USDA Zone 4] .

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Entries in perennials (152)


The Flower Garden Style of Piet Oudolf

Image copyrighted by Scott Weber. Used with permission

Scott Weber, of Portland, Oregon, has been designing and planting flowerbeds around his property for several years. Above and below are two of the many stunning photos he shares with readers on his blog Rhone Street Gardens. The images of his mini meadow-like plantings always take my breath away no matter how frequently he posts. Scott once mentioned that Piet Oudolf inspires the spirit and design of his garden.

Image copyrighted by Scott Weber. Used with permission.

For over one hundred years, the English flower garden remained the championed design for colorful gardens in the Western world and I confess that it remains my personal favorite to this day.

Nevertheless, by the time the twentieth century began to overlap with the twenty- first, along came Dutch garden designer Piet Oudolf to nudge that traditional style out of its spotlight. Today, when I combine some of his design elements into my English-style projects, the results are quite moving.

Many books and articles have been written about this extraordinarily talented garden designer and I expect that ongoing and well deserved worldwide tributes will continue for some time to come.

Garden design by Piet Oudolf. Click on image to visit site.

Piet Oudolf has succeeded in replaced the traditional perennial garden with landscapes inspired by the chaos of wildflowers, the assorted textures of foliage and the ethereal movement of grassy meadows. Yet, there is nothing chaotic or wild about his gardens, even if he does include native perennials in his layouts. In fact, his unique gardens are the results of meticulous, intricately designed planting schemes which, when repeated over vast swaths of land, create mesmerizing rivers of lush plant compositions.

His strategically arranged garden blueprints are realized primarily with robust, broad and small leaved perennials, bulbs, and ornamental grasses - all placed into recurring matrices to create a blissful flow of colors, textures, flower shapes and plant forms. Tall species, as well, are incorporated into some of his flowerbeds so that visitors can feel enveloped as they walk under and through his compositions.

These design elements also include the structural skeletons and seed heads of plants that provide visual interest when gardens are usually dormant and bare in winter. In Mr. Oudolf's gardens, eye-catching details attract and engage visitors all year round.

The High Line, New York City, gardens by Piet Oudolf.

Some of Piet Oudolf’s works are located in private gardens and privately owned parks open to the public. However, his best-known and powerful creations are situated in the public spaces of large cities. These urban projects create stirs of excitement when they first open and leave an enormous positive impression on the public. The result is that he has become an iconic figure in the garden design community.

Salvia beds designed by Piet Oudolf at Lurie Gardens, Chicago

One finds these urban oases in some of the largest and most densely populated areas. Here, juxtaposed among concrete, steel and asphalt, are wild meadow-inspired flower gardens whose soft natural and seemingly random appearances contrast dramatically with the disciplined, sleek and hard surfaces of the city structures that surround. They serve as a therapeutic refuge from the stress of daily life.

Lurie Gardens, Chicago.

As a highly respected designer and mentor, he continues to influence the work of prominent landscape designers on both sides of the Atlantic and his philosophy inspires home gardeners, some of whom live in climatically challenged areas where native plants and grasses work better than other perennials, to create dramatic yet beautiful traffic-stopping gardens.

Oudolf’s designs are synergistic; the compositions are more sublime than the appearance of any one of his chosen plants when grown alone. In his gardens, we experience the exquisite beauty of nature that can transport us from demanding urban existence to a destination overflowing with spirituality and hope.

Admire twenty six completed garden projects by Piet Oudolf at his website

Watch a video of his work for New York Botanical Gardens


A Purple Autumn Perennial That Pops: Vernonia Lettermannii

Photo credit:The University of Tennessee, Institute of Agriculture

A client gave me a mandate to enhance her flowerbed whenever I find a reliable perennial that blooms in purple.

To please her, I scour my suppliers’ catalogues every spring looking for purple blooming plants. Then I test grow them for a few seasons to determine how they perform. Most are disappointing.  A few become messy or invasive. Some are short-lived plants lasting one or two seasons while others are unable to survive climate conditions in my growing zone.

Happily, this year I discovered that the recently introduced Vernonia lettermannii  - also referred to as Narrow-leaf Ironweed - meets my rigorous requirements for neatness and low maintenance. I intend to surprise my client by planting it in her garden this coming spring.  

Photo credit:

Although it is dramatically shorter than the species Vernonia arborescens or the variety Vernonia mammoth, lettermannii provides a far more intense color display than either of its taller cousins. It blooms in August and September in a bright true purple that projects from afar and happily holds its color in the August sun.

Unlike its taller relatives that fade as they age and shrink from view, the florets of lettermannii hold their form and maintain a vivid color [albeit slightly more reddish] long after dormancy sets in. By October, the flower heads may have long expired but their rich color, now on slightly scrunchy petals, sustains itself for another few weeks.

Here are several photos from this past season of Vernonia lettermannii  in one of my October flowerbeds:

Vernonia lettermannii satisfies gardeners’ needs on several fronts. It is a butterfly and hummingbird magnet. It feed a passion for purple flowers both when in bloom and into creeping dormancy and it enriches the color story of the autumn garden by extending the bloom season well into October.

photo credit:

An additional attribute is its magnificent feathery foliage. In late spring, the perennial shoots up to create a large, soft mound of glossy-green foliage that is enchanting to behold and heaven to touch. Throughout the growing season, this visual delight continues to add to the garden a] sumptuous architectural detail - think round but softer boxwood plants - and b] feathery sensuality like Amsonia hubrechtii.

Cold hardy in USDA Zones 4  [CND Zone 5] Vernonia lettermannii is a heat tolerant plant that grows two or three feet tall and wide in full sun, even in poor rocky soil, under average to dry conditions. Good drainage is required. Periods of inundation are tolerated, but not heavy or saturated soils.

Few if any retail nurseries stock Vernonia in any of its varieties. Consequently, all the varieties growing in my garden were purchased from mail order suppliers.

Here is how online seller Plant  describes this flowering perennial :-

Vernonia lettermannii is a fascinating ironweed that hails from Arkansas and Oklahoma where it can be found in rocky soils and on rock outcrops. Imagine taking an Amsonia hubrichtii, shrinking it to 2' tall x 2' wide, shearing it into a round ball, then topping it with hundreds of purple flowers in August and early September, and you have Vernonia lettermannii...a hummingbird delight. We grow this in our hot, dry, scree garden where it has caused visitors to lust in their hearts.

The seller’s words above are not hyperbole. Although the variety lettermannii  is much shorter than the species, it  produces a far more dramatic color display than any of  its taller cousins and it holds that color long than they do - even after it goes dormant.

At that time of year, while the gardener is mournfully anticipating the falling leaves of autumn and when there is little or no color left in the fall flowerbed, Vernonia lettermannii can cheer the heart and  take one’s breath away.


This Visitor Deserves a Gardening Blog of Her Own

Front porch. Image copyrighted by Sheila Robertson, Scents and Centsabilty.comA recent visitor to my blog has taken a very long journey through all of my posts. Sheila, who signs as Orchard Annie, leaves comments that reflect a reader with a passion for gardening who truly deserves a blog of her own.

The play yard. Image copyrighted by Sheila Robertson, Scents and Centsabilty.comI was so impressed with the breadth of one of the comments she posted that I contacted her to ask permission to use them as a freestanding guest blog. Her advice, written in a unique, folksy style, was a reaction to Part 3 of a three-part post that first appeared here in 2009. In that series, I advise readers how to create beautiful landscapes using perennials and flowering shrubs. I titled it How to Paint a Masterpiece in the Garden.

A spring flowerbed. Image copyrighted by Sheila Robertson, Scents and In Part three, I dealt with the monetary aspect of perennial gardening. Click to link to that article:  

Image copyrighted by Sheila Robertson, Scents and Centsabilty.comBelow are suggestions that Sheila added to my post about designing a perennial garden on a budget. Although I have done some minor editing for flow, most of the text is in its original form so that readers can get to know her, as I have, through the personality of her writing style. All of the images above that illustrate this post belong to her.

Expansion on your budget ideas.
1) Intersperse low, wide growing evergreens. The tiniest pots can be had for $5 at big box stores. They take being overrun or severe pruning so that in the case you have to move or get too busy or ill to take care of a flowerbed there is a gorgeous plan B waiting to be revealed.

You must look upon your garden as a hobby, not a property value return. I cringe to recall my sister-in-law sodding a beautiful yard because she wanted to spend time camping  with the kids on weekends and not to be stuck taking care of the yard. A high maintenance yard can actually lower the selling price of a home.

2) Multi colored collection of fall planted bulbs (crocus, Spanish blue bell, etc.) can be found at very reasonable bulk prices. Plant them wider than recommended and be patient, in 4 years you will be able to transplant them into those lovely solid colored drifts displayed on magazine covers.

3) If you see a garden you adore, make a habit of taking your walks on that route. Surely an avid gardener working in their yard loves a compliment and eventually will share their knowledge and their plants. I often supply grocery sacks for complete strangers. Take along some plastic sacks in your pocket (for the pooch right?) and a Sharpie to write on the sack the name and height of the plants you receive. If you forget the particulars, you can type in an image search on Bing for some good examples of what to combine them with, along with care instructions.

4) Alan Titchmarsh had a "Love Your Garden" episode (I love YouTube!) on a man's room after room of exceedingly formal clipped and topiaried gardens where monochromatics were stunning. You cannot convince me that formal gardens are budget though, how anyone keeps a whole yard of box or yew uniformly healthy is not possible to imagine.

5) Plant permanently. Some combos are low maintenance forever heaven. I bought bulk mixed, 4 months of bloom, daffodils from Brecks - (order a catalog, a coupon comes with it, and if you start an online order then decide the price is too steep and delete it before the payment is sent they'll sometimes email a coupon) -  and interspersed them with budget daylilies chosen for their bloom time, color and heights.

Gilbert H Wild and Son have hearty bare rootstock day lilies and though the new varieties are pricey, older ones can be had for $2.75. When daffodils fade, the day lilies completely cover the withering foliage (no clean up!) - both daffodils and day lilies are long lived perennials that tolerate total neglect. - (Don't put nitrogen on day lilies or you'll get all foliage and no flowers.) – Eventually, this combo will choke out any and every weed, even grass. As with all perennials after bloom, I chop the entire day lily plants down to the ground: they soon send up foliage as fresh as springtime. In this bed, I will be able to take the bagging lawn mower over the entire island.

6) Plant a hedge if you cannot afford a fence. An appraiser told me a board or like fence will retain it's value in resale, chain-link fences will recoup half of their cost, and a filled in hedge will add as much value as a board fence to your property's value.

Research what grows best in your area. I planted a big box emerald green arborvitae and then discovered a Wisconsin native, that I found later, that was much more vigorous and care free. I bought the smallest size shrubs and carefully plotted out placing them to compliment what my neighbors had in place so they would look less awkward while puny. The wind and sun scald they suffered [and which stunted them] stopped when I started applying Cloud Cover (a polymer that slows evaporation) before the temperatures dropped below 40F. The manufacturer of that product also recommends applications throughout the growing season to decrease watering.

7) Look beyond your own perimeter before planning. It may be tempting to nix an unattractive shrub but probably a previous homeowner put it there in order to hide an unpleasant view. Likewise, there could be an attractive view waiting to be borrowed from next door or the horizon if you carve out a frame for it.

8) Research the varieties of plants present in your yard. Many shrubs respond thankfully to renewal pruning, and many crowded expensive perennials look like a bed of weeds for want of transplanting.

9) Learn how to prune and don't be afraid of it! You will increase the beauty and lifetime of shrubs and trees twenty fold as well as keep the size in check, but it must be done before the point of no return.

Likewise, don't feel heartless about discarding the remnants of flowers you've divided. Overcrowded borders do not perform to their full potential: you will get frustrated and feel you must start from scratch with a whole new planting scheme.

If it makes you feel better put divided plant discards in a cardboard box at the end of your drive marked "free, variety, color and height."  If they don't disappear, which would surprise me, take them to the municipal yard waste site and set them slightly apart from the pile. If no one takes them, the pay loader there won't object to adding the cardboard box to the compost heap. A friend with a lawn care business collects all the plant divisions he can get, piles them into his work yard and waters them until he gets a request for a garden.

10) Pruning lessons: I got over my fear working at my father-in-law's apple orchard "Don't worry, you can't kill them," he said. Volunteer at a municipal garden, where you will be greatly appreciated and where you find out which tools suit you best before you buy any. YouTube has several wonderful tutorials from all parts of the country on every variety of plant.

11) Scour the classified ads in Spring. Garden clubs hold plant sales as fundraisers, and the prices are so right! Arrive early if you can: members pot up slips from their own gardens, sometimes it's the "I shouldn't have splurged" rarest, priciest plants that they share.

12) Consider long-lived edible plants. I have ruby stemmed rhubarb at the end of a ferny asparagus hedge. The rhubarb stays lovely as long as I reach in to bust off the flowers stalks as they appear, and if the leaves get tired or crowded looking, they make swift single layer mulch that dries to earth color in a few days. The asparagus backs an Asian gravel garden with stone "islands", a Buddha temple, and bamboo fountain, redbud, Siberian iris, and dwarf conifers. Both the asparagus and rhubarb blend nicely with that theme....and the best part is that both plants are the first flavors of Spring!

Thank you, Sheila/Orchard Annie, for your input. To introduce her to my readers, I requested that she email some photos of her garden and a short biography. I was not prepared for what I received. She sent me enough mouth-watering images of her horticultural work to create many interesting garden blogs and her biography revealed a romantic narrative about the role of men in her gardening life. I will share that lovely story in a future post.

Readers who recognize Sheila's talent from the photos she supplied, and from her original and intimate style of communicating, are invited to leave a comment below to encourage her to create her own blog.

Visitors who missed out on my three- part series can link to Part 1 and 2 here:

How to Paint a Masterpiece in Your Garden Part 1

How to Paint a Masterpiece in Your Garden Part 2


Plants That Perform All Season, a book review

Powerhouse Plants, 510 Top Performers for Multi-Season Beauty, Graham Rice, Timber Press,

Graham Rice is an international renowned and respected plantsman with gardening experience on both sides of the Atlantic. He is also an award-winning writer with more than twenty gardening books to his credit.

This latest work reaches out to readers who garden on small plots of land where plants must do double duty because there is room for so few of them. To create beautiful and interesting gardens under these confining conditions, Mr. Rice recommends that we consider using versatile powerhouse plants.

Such plants enhance the design of small gardens because they multi task throughout the growing season. Included in this category are perennials, shrubs, trees, ornamental grasses, vines and ground cover, all of which put on visual performances that last longer than their respective plant tags indicate. They do that by transforming themselves from a flowering summer perennial, for example, into a display of intensely colored fall foliage.

The inherent potential of these versatile players allows the gardener to create different and evolving plant combinations for various times of the year, all the while using a minimum number of plants.

Readers will be delighted that the author’s suggestions are confined to ones that are easy to grow, hardy, and glorious performers. Nothing makes a gardener happier than to discover that a beautiful plant is also a workhorse and that it requires little attention.

In that respect, nature has been very cooperative. Mr. Rice has managed to identify no less than five hundred and ten of these powerhouse plants – each with characteristics that evolve or linger in the garden, and whose beauty and visual interest is sustained long after they have lost one of their salient features.

Such a plant will display at least two of the following attributes: - spring shoots pushing through the soil, fresh unfurling foliage, spring flowers, summer flowers, summer foliage, attractive fruit and berries, evergreen foliage, vibrant colors in the fall, bark, interesting and colorful stems in winter, and winter or spring foliage rosettes.

Of course the above list doesn’t even begin to address other characteristics that a plant make contribute to the garden. These would include form, shape, texture, movement, fragrance, birds, and butterflies. All are qualities that enhance the value of most of the recommended plants in this book.

Gardeners who struggle to maximize the visual appeal of their small gardens will be relieved that there is now a handbook to help make that an easier task. Creative homeowners with larger gardens will also benefit because versatile, all-season, powerhouse plants enrich the appearance of all gardens, regardless of their size.



How to Solve Growing Problems in the Garden Before They Begin

Why Plant That When You Can Grow This? 255 Extraordinary Alternatives to Everyday Problem Plants, Andrew Keys, Timber Press.

In our quest to recreate luscious landscapes we have visited, or studied in a book or magazine, we sometimes find our personal gardens filled with plants that make us unhappy due to their disappointing appearance or performance.

Our growing zone may be too hot or cold, the soil on our land too wet or arid, and the sun might be to searing or absent altogether.

Even when the conditions are perfect, surprises still occur. Too much rain or too humid a summer will result in mildew. Pests that we did not expect to attack our plants often arrive out of nowhere.

Some perennials will propagate themselves aggressively, others require more nutrients or irrigation than we can provide. Sometimes we become overwhelmed when we realize that a plant requires more maintenance than we are perpared to undertake.

Our frustration with plants that disappoint is exacerbated by our growing need for predictability and reliability. Many of us have a compromised life style that does not allow the luxury of time to fuss and fiddle over plants.

The solution:- Read this book!

In it, the author suggests we adjust our expectations. Instead of recreating someone else’s landscape, he recommends that we interpret it by using more reliable, less invasive, and easier-to-care-for plants.

Mr. Keys, as his title precisely states, presents 255 user-friendly plants for our consideration. While readers in colder climates are expected to skip over those that are inappropriate for their growing conditions, there remain enough choices for all gardeners, regardless where they are located.

Readers will discover

  •  replacement plants for twenty trees that might be problematic,
  •  substitutions for twenty-five shrubs with specific growing problems,
  •  alternatives for seven vines that may give the gardeners a headache,
  •  options for twenty-two perennials that are challenging to grow or maintain,
  •  better choices for the twelve grasses and ground covers a gardener should avoid.       

To facilitate the reader’s ability to deal with these horticultural issues, Mr. Keys has supplied the names of web sites for supplementary, elaborative information, as well as a list of recommended readings, mail order plant sources for American and Canadian gardeners, and an easy-to-consult conversion table for gardeners who are stymied by either metric or Imperial measurements of plants.

This publication is another in a series of useful garden manuals. Those of us who lead busy live are always happy to be alerted to potential horticultural problem. It is reassuring to know that we can solve them before they become full-blown headaches.