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Sheared: Part Two

Anyone who chooses to look up topiary plants of distinction on their computer will find no end of articles with pictures of grand gardens featuring breathtaking topiary plants.  Many of them have been cultivated long enough to have acquired shrine status. The size and scale of many of these topiary plants is staggering, never mind the work that is involved in keeping them up. I enjoy seeing them as much as the next person. But I also have great admiration for gardeners who on a more personal scale grow on plants that require a substantial and steady commitment to the maintenance. The single ball boxwood topiaries that are pictured above began as fairly modest plants grown at a farm specializing in boxwood in the Pacific Northwest. My memory is of a head diameter of perhaps 10 or 12 inches. The trunk would have been in the neighborhood of a quarter to a one half inch caliper. When these topiaries arrived, their trunks were secured to bamboo stakes virtually identical in size to the trunk, and as tall as the the stem and head. This is smart staking. The head of a topiary is the most vulnerable to catching the wind, and snapping off. Young topiaries are fragile. If you expect to grow them on, protect every part of them, bottom to the very top. I can’t say exactly how long we wintered these trees for my client, but it may have been 8 years or so.  They summered in pots, and wintered in our unheated garage space. We were taking no chances with winter weather. Did we do the yearly pruning?  No. We farmed that job out to an expert.

These topiary starts of lemon cypress- cupressus macrocarpa Goldcrest “Wilma” will top out at 3 feet or so. Outdoors, in a zone 7 or warmer, Goldcrest can grow to 16′ tall or so. The dwarf version Wilma makes a good house plants, provided they have a really sunny south facing location for at least 4 hours a day over the winter. They like cool temperatures, so wintering them over in a house kept at 72 degrees can be a tough go. Like most cypress, they appreciate evenly moist soil. If you let the rootball dry out, you have lost the plant. It is the juvenile foliage that has the best lime green color, so regular trimming will preserve that color. They appreciate a summer outdoors, but I try for a full sun morning with a little protection from the worst of the afternoon sun. Be advised that each stem you trim will probably turn brown at the cut. But once that branch starts growing again, that cut mark will fade from view. This is a quick look at the care issues with lemon cypress. Should you have the idea to grow them, look up their culture on line, and read.

No topiary in our zone is more challenging to grow than a myrtle. Myrtis communis compacta is an evergreen shrub that is especially genial and tolerant of frequent pruning. What they are not tolerant of is dry soil. During the winter, they need bright light, and even moisture. Myrtle topiaries of the scale and size pictured above requires a passionate and faithful grower. I have not seen myrtle topiaries of this size and scale very often, but I can attest that these clients lavished no end of attention on them.

Certain trees are quite tolerant of close pruning. The carpinus pictured above has been expertly trimmed by a virtuoso with shears. I am quite sure there was a lift involved. They respond enthusiastically to pruning. This sheared shape is close to the natural shape of the tree, meaning the health of the tree is not endangered. A tree is a vast subject for a topiary, but the time between prunings can be fairly long. Linden trees are equally amicable about this kind of pruning. The boxed lindens on the driveway at Detroit Garden Works are pruned every other year at most.

Limelight hydrangeas make gorgeous single ball topiary plants. The loosely spherical head in full flower is quite spectacular.  As hydrangeas are naturally very coarse growing plants, their shape is a study in contradictions. They are informally formal. Our grower trims the hydrangea standards twice a season. Once in late March or early April, and again later in May. This schedule helps to produce a strong network of branches that helps keep the flower heads aloft. Even so, we often tie up the branches with stretch tie, to make sure the framework is strong. The stake is as tall as the very top of the plant.

Italian cypress is not hardy in our zone-how I regret that. But if a client is willing to winter them over in an unheated greenhouse they can provide a dramatic focal point to a container for a number of years. This evergreen is naturally very narrow and conical, so the pruning required to keep them tight is a matter of emphasizing and more clearly defining what is already there.

This young boxwood topiary is delightfully under scaled for its under planting. The boxwood head has not been sheared, but left to its natural devices.  It gives a very traditional landscape form a much more contemporary look.

Yews make good topiary subjects, although they do not respond as well to close shearing. This double ball taxus lived for 4 years in this pot, all year round, before succumbing to a particularly cold winter. A little looser treatment produces a better looking plant. As in green through and through. Drastically sheared yews are common in the landscape, but the development of a topiary form is not a goal. It is a once a year effort to exert control over a plant that may be poorly sited. Improperly sheared yews sporting a thin skin of green, and bare branches and trunks underneath is not a good look. It also contributes to the decline and ill-health of the plant.    Junipers are rough coated evergreens, but they respond surprisingly well to pruning.  They are also happy with a long term home in a large container. They are low maintenance shrubs and trees in general, so they shrug off the shearing.

Westringia fructicosa, commonly known as Victorian rosemary, is a dwarf shrub that responds well to development as a topiary. I rarely see it offered for sale, which is unfortunate. This particular single ball topiary made a beautiful container specimen.

Culinary rosemary, or salvia rosemarinus, is a well known subject for topiary. The clippings smell delicious, and its use as an herb is legendary. This particular unsheared topiary is underplanted with fiber optic grass and strawberries.

specimen single ball rosemary on standard

coleus topiary

double ball eugenia under planted with begonias

double ball boxwood topiary under planted with curly parsley

variegated Algerian ivy topiary

unsheared double ball rosemary under planted with lettuce and pansies-perfect for a spring container planting.

Posted on: May 9, 2020 8 Comments
Filed Under: Detroit Garden Works, Woody Plants, Plants, container planting, Deborah Silver and Co Inc Tagged With: , , , ,

Shear Pleasure: Topiary

 

Gardeners have been pruning plants just as long as they have been growing them. It isn’t too hard to figure out why. A broken tree limb or dead cane on a rose needs to be cut off, as dead branches are just plain unsightly. A wild hair of a shrub branch hanging over the walk can and should be trimmed out of the way. The branches of lilacs, roses, hydrangeas and other woody plants that cross over one another have the potential to damage one another. Every branch of every plant moves, given the natural flow of air. Bark that gets worn down to bare wood endangers the health of that branch. Healthy shrubs, meaning properly pruned shrubs, have a branch structure that permits the free flow of air and light. Sometimes a little intervention helps to encourage healthy growth. I am sure you have noticed, that in the wild, there is as much dead as there is living going on. Some branches can be infected by disease. Removing that diseased portion helps to insure the health of the rest of the plant. Some plants eventually grow in to each other’s space. Some pruning can be best described as refereeing.

Lilacs are woody shrubs that greatly benefit from a pruning overhaul. Removing the 3 largest branches at the ground level every few years of a mature and sizeable lilac keeps the plant youthful. This is a shrub that greatly benefits from a turning the old growth over. New branches that sprout from the ground level will grow fast, and bloom profusely. Old branches become leggy, woody, and tall, and produce few blooms. Old unpruned lilacs are notable for their abundance of dead branches, thick woody growth, and pitifully small and sparse blooms 15 feet or more above ground. Regularly pruned lilacs are more compact, and bloom heavily. Great looking lilacs require regular pruning. Once a year to shape and rejuvenate. And a second time to remove the dead flower heads. Other shrubs, notably oakleaf hydrangeas, do remarkably well with no intervention whatsoever. I have a single shrub almost 25 years old that I have never touched with a pair of pruners. It is lovely, and blooms well every year. Some plants decline with pruning. I would not prune an American dogwood except to remove a dead branch. Excessive pruning on maple trees expose ordinarily shaded branches and trunks to the glare of the sun, resulting in scald.

To prune or not to prune, and how to properly prune for health and well being, is a topic with considerable coverage on line.  Any gardener wanting a consultation on pruning practices for any given plant can find numerous articles available to read. General articles about pruning are invariably too general. Not all plants respond well to generic pruning. This seems obvious to me, but apparently not to all. A good look at any landscape where every shrub cultivar is pruned to the same shape and size will tell that sorry story. The human hand armed with hedge trimmers set to a one size fits all is not about gardening. This is about a spring housekeeping chore executed by an unwilling and irritated housekeeper. A once a year housekeeper, mind you. The results are visually embarrassing, and can endanger the plant. That said, gardeners have been pollarding trees and coppicing shrubs for centuries. Every story has at least two sides, does it not? Once you have read about how to prune a plant for health and well being, decide what you believe. Or sign up for what appeals to you. Or follow a plan that seems most logical and sensible. As a first and a last resort, adapt what seems in keeping with your style of gardening, and wade in. Plants are remarkably resilient. I have seem them recover and flourish in spite of very heavy handed and misguided pruning.

This is by way of saying that no one needs my opinion about how to prune. My pruning practices are the result of decades of experience. By this I mean, trial and error. It is not a bad way to learn. Plants are incredibly tolerant of almost everything you have to dish out. My pruning practices work for me-and not necessarily others. A gardening friend of mine cuts her spireas and other fast growing deciduous shrubs to the ground in the spring-so they don’t get out of hand and grow too tall. I am sure no pruning article would recommend this, but it works for her. If you have a mind to try this, prepare ahead for a look you might not like. There’s always next season. Or try it by a half. Or try it with one plant. I have pruned hydrangeas by 2/3rds and  by 1/2. I have left them unpruned. I have given them shag haircuts. They still perform beautifully. As if they were unaware that I had done anything.  If they are woody and leggy, I prune some branches harder than others, to encourage some green sprouts at the base. This year, I have not touched them. I prune based on what I am in the mood for.

If you like to prune for the shear joy of pruning, then topiary plants are a perfect plant. Topiary is the art of pruning plants into various geometric shapes. Some plants take well to regular shearing, and respond to training better than others. The myrtle topiaries in the pictures above are woody shrubs. They are not hardy in my zone. A summer outdoors in a fairly sunny place can be followed by a winter indoors in a spot with decent light.  Training them to grow into a a single trunk takes a bit of skilled work, and a good bit of time. Rob buys plants already trained into topiary forms every spring. Taking over the care of an existing topiary is infinitely easier than starting from scratch. They are irresistibly delicious to any person of a gardening bent. That said, no myrtle topiary will tolerate going dry. Do not buy them if you are not a watering sort.

Lemon cypress is a very large vertically growing evergreen tree that is very tolerant of pruning. They make great topiary plants at a young age. Shear away. I had a pair that I shifted up into larger pots every year for 5 years. At that point, I had to let them go. I had no winter storage that could handle them at 5 feet tall, and 2′ wide. But the five years I had them was a relationship I treasured. I learned how to clip each branch individually. The time I spent clipping was relaxing and absorbing. It was a challenge to clip evenly to a finished and beautiful shape. I most certainly would grow them outdoors if I could, and I would prune them on a larger scale.

All of Rob’s topiaries are in a fairly shaggy state right now. I like this state of a topiary best of all-the anticipation of the haircut to come. I have been known to study a topiary for a week before I break out the shears. I see gardeners do this all the time. Their boxwood spheres and cones, their juniper spirals, their Christmas trees, their lantanas,  their lindens and their hornbeams – the pruning is an event.  Topiaries do demand regular pruning. They demand all of what you have available to give them. That is part of their charm.

Rosemary makes for an ideal topiary. They take well to pruning. The clippings can be added to the cooking du jour. The smell of the cut stems is strong; piney and divine. The oil from the stems perfume both the hands and the shears. The fragrance of rosemary is treasured by gardeners.

Lavender is marginally perennial in our zone, provided a long list of requirements are met. I have planted countless numbers of them, most of which perished within a few years. Lavender topiary in pots provide a way to enjoy lavender without all of the pitfalls that come with an in ground planting. Like rosemary, the cut stems perfume the air all around it. The flowers are modest in size and color, but a lavender in full bloom is glorious. A lavender topiary in full bloom is a cause for celebration. Likewise, a beautiful topiary plant. Beautifully grown and trimmed topiaries are strong evidence of the gardening hand. How I admire the work and dedication that goes in to them.

If you haven’t yet, try one. If you do grow topiaries, bravo.

 

 

Posted on: April 29, 2020 23 Comments
Filed Under: garden sculpture, container planting, Woody Plants, Detroit Garden Works Tagged With: , , , ,

All Hellebores Great and Small

My first exposure to hellebores was likely in the 1970’s. Though gardening consumed every available moment and most of any available cash I had for plants, there were no hellebores in my yard. I could buy five other plants for the money it took to buy one hellebore. My Mom, on the other hand, being much more solvent than I, had an ever expanding collection. At first, I could not understand her fascination with them. Topping out at a foot or 16″ tall, it took 5 years to grow on a decent sized clump. The foliage was certainly attractive, but the flowers left quite a bit to be desired. Enjoying them was a necessarily interactive experience. The flowering stems were lax and thin. To enjoy them, one needed to bend over to half one’s height, pick up the drooping bloom, and turn it skyward. As pictured above, helleborus x hybridus varieties of old provided the gardener an excellent view of the flower’s backsides. The one flower looking at you was a bloom that I cut, and laid face up on the plant. Not that the back wasn’t beautiful, it just did not provide the thrill of a full front view. As in, face to face.

The flowers were about the size of a quarter or half dollar. They were broad and weighty compared to the stem. No wonder the flowers were nodding. Another more compelling reason for their down facing blooms is practical. Upfacing large flowers can suffer damage from rain and rot, that could interfere with the production of seed. The stalk attached to the flower is known as the peduncle. This word itself suggests something robust and strong, but the stems of these hellebore flowers could not have held a flower in the upright position. It always amused my Mom when I would lie down on the ground next to one of her plants, and try to peer up at the flowers. The colors of the flowers were equally as unsatisfying. The thin petals of the white flowered strains were a dirty white, most likely due to their translucence. The reds were overlaid with green, and the pinks were anemic.

My Mom, however, was delighted with all of them. In retrospect, I attribute that to her taste, experience and sophistication in regards to garden plants. I had none of that going for me, in my 20’s. She thought her hellebores possessed a quiet and diminutive beauty. She organized an entire garden around them, and that moment when their blooming would kick off the spring season. There is something to be said for old fashioned flowers, whose size, stature, substance and color has not been tinkered with by a breeder. There are those who prefer the old fashioned feverfew to their button style double counterparts. Single flowered hollyhocks are so beautiful. The double flowered varieties look alarmingly like tissue papers suitable for a parade float.

The irregularly blushing coloration of this Royal Heritage strain hellebore flower is charming, not arresting. I was lucky to have a single flower, by virtue of the support provided by the flower bud below it, face out. Otherwise, I would have no idea what the flowers look like. What a shy group this is!

This rose pink seed grown hellebore from the same strain has small rather pointed petals that do not overlap so much. This particular plant has more side facing flowers than nodders, so it is easier to enjoy.

This is one of my favorites from this old fashioned group. I picked the flower, and set it on the ground to photograph it. This is a good photograph for identifying the flower parts. What appear to be pink petals are actually modified petals known as sepals. Most flowers drop their petals one they are fertilized. But these pink sepals will age to green, and persist on the plant for many weeks. A group of sepals form a calyx, the purpose of which is to protect the flower, and its reproductive parts. The actual flower is comprised of short petals that have rolled up, closed, and formed tubes, or nectaries. In this picture, the nectaries are those green crescent shaped forms that encircle all the reproductive parts. The stamens, or male reproductive parts, have anthers at the top, which hold the pollen. They appear as cream white dots in the above picture. The female reproductive parts, the pointy shaped carpels, have not grown out yet. When they do, they will grow and enlarge into what will become the seeds. The sex lives of plants is complex and fascinating-and requires the assistance a third disinterested party, as in insects, wind, or bees.

The newer cultivars of hellebores are quite astonishing.  I still remember the first time I saw a yellow flowered hellebore. I could hardly believe it was real. The above pictured hellebore from the Spring Promise series is called Sally.  It is a robust grower. As many flowers face out to the side as face down. Outfacing flowers are still able to shed rain water, limiting rot in the center of the flower. More flowers than not have 7 sepals, as opposed to the old fashioned 5. There is a good bit of overlap to the sepals, resulting in color that is richer and more brilliant.

The size of the flowers is considerable larger than those on my older hybrids. 15 flowers of this size gives the plant the impact of a small shrub.

Also a member of the “Spring Promise” series is this named variety, Connie. The white sepals have plenty of substance, meaning they are thick enough to read bright white. The spots are a striking visual plus. I am sure there is every bit of 150 stamens on this flower. There are so many, the nectaries are almost completely obscured. It has an exotic, rather than charming appearance.

From the hybridizing efforts of Marietta Byrnes, her “Winter Jewels” strain known as Jade Star” features green flowers with maroon red markings and picotee edging. The original plants in her strain have large areas of plum and wine red over the green, but seedlings can vary considerably from the original.

This is another version of Jade Star. Since hellebores from a strain do not come true to seed, it is best to pick them in flower so you know exactly what you will get. That said, I like every version of this moody colored hellebore strain I have seen.

The double flowered hellebores are indeed showstopping. This particular plant is from the helleborus x hybridus Winter Dreams series “Elegance White”. In all the years I have had it, it has increased only modestly. But as reluctant as it is to put on weight, it is breathtaking, and well worth the wait.

This double pink hellebore is also from the Spring Promise series, and is called “Frilly Kitty”. 7 years post planting, it is spectacular in size and bloom this year. Hellebores of any genetic background increase slowly, so the cost of good sized plants is considerable.  This cultivar is vigorous and healthy, and gets no care from me besides supplemental water when it is dry. This is breathtaking example of what modern hybridizing has achieved.  Is it better? I like having a range of cultivars both great and small.

I cannot remember your name, but I am happy to be hosting you in my garden.

Posted on: April 16, 2020 27 Comments
Filed Under: perennial plants, flowers Tagged With: , , , , ,

The 2020 Hellebores

The hellebores do not have to compete very hard for my attention in the spring. They are just about the only perennial game in town come late March and on into April. I will admit I am out there searching for signs of them when the ground is still frozen solid. I am an enthusiast, yes. They are well worth the wait. Helleborus X hybridus-a group thought to be made up of 14 to 16 other species – is quite hardy in my zone. Other species and their hybrids, notably helleborus niger, are a little touchy for me, but well worth a try. The large leathery leaves populate sturdy compact plants, and are a rich dark glossy green. That foliage not only makes for a fine overscaled ground cover in shadier places throughout the growing season, it persists well into our winter. They prefer compost laden soil, regular moisture, and part shade conditions. That said, I have grown them successfully in full sun, and in deep shade. They are most obliging.

In an especially wet year, I will see some botrytis, but in general, the plants are healthy and hardy. They are slow to put on weight, but once they do, they bloom profusely. They are very long lived. I have more than a few that are better than 20 years old.  I hear they are not so happy to be divided, so I have stayed away from that. Their bloom story is equally as interesting.  The thick juicy flowering stalks emerge first in the spring. Each flower is surrounded by leaflets. The flower shapes and colors, given intense hybridizing efforts all over the world, are incredibly diverse. Black, white, green, red, yellow and pink are all represented in varying shades and combinations of shades. Flowers can be single, anemone flowered, or double. In my opinion, the single flowered varieties are the most persistent and longest lived. The doubles with huge petal counts are fascinating, but the singles are my favorite. A green flowered single is my favorite of all.

Once the bloom period is well underway, the plants send up new foliage. The foliage pictured above is the remains of the previous year’s leaves. In a perfect world, I would cut off the previous season’s leaves just prior to the flower stalks emerging. Should I miss that moment, I try to wait until the flowers are well out of the ground. Few gardening mishaps are as frustrating as cutting off soon to flower stalks by accident. I have done it more times than I care to remember.

What you are seeing above is a trim long past due. The scraggly brown leaves of yesteryear are not adding much to the flowering stalks coming on. David usually cuts the old foliage off, as it would require that I leap over the boxwood hedge to get within snipping distance.  At 6′ 3″ tall, he is able to step over. But he is at home in his own garden, tending to his own hellebores now, as well he should be. So I am stuck with a view, and not a presence. As it doesn’t bother me enough to risk getting there, I am intrigued to see how the plants will handle the chaos.

Several weeks in, it does not appear that any of these flowering stalks are hanging back or hindered by the lack of a cleanup. They actually seem quite indifferent to the mess. This is a rather unattractive moment, but it does illustrate the the process of nature cycling from one growing season to the next. Were I to try to get in there now and try to scoop up all the detritus, I feel every plant would be glaring at me. Years ago a friend with an extraordinary wildflower garden told me she worked very hard to see that her garden was undisturbed by her presence as much as possible. She limited her house keeping to the removal of downed limbs and branches, and all but a reasonable layer of oak leaves in the fall. Her garden was stunning. Large drifts of the same plant took hold in those spots optimal for their success. It had a relaxed and natural appearance as it was minimally and judiciously tended. Plants that have been fussed with too much have that look about them.

This area will surely test that hands off experiment. This first of this group of hellebores were planted decades ago. Should one succumb, I plant another. It is a spot that I can readily reach. But I am interested to see what will come of a hands off approach.

This old clump of Royal Heritage strain will have lots and lots of flowers.  At this stage, it is hard to imagine this plant occupying every bit of four square feet. As they are planted on the north side of a sizeable picea mucrunatum, they are slower to come on in the spring.

All of them seem to be putting forth fresh growth.

This stage is every bit as beautiful as the flowering stalks fully flushed out.

Is this a better look? I will soon have an alternate treatment available to look at.

It could be by the time this hellebore is at this particular stage, I will barely notice what did not get done.

 

Posted on: April 8, 2020 25 Comments
Filed Under: Spring, perennial plants, garden maintenance Tagged With: , ,