Shear Abuse

Cascading rosemary should actually cascade rather than get shorn into submission. (For this situation, it is subordinating to the climbing Boston ivy below.)

You can make fun of the decadent hair styles of the 1980s all you like; but you must admit that they were better than what came later. Back then, the assets of each particular type of hair were exploited instead of destroyed; sculpted instead of chopped into submission. Sadly, landscape maintenance evolved in a similar manner.

So many trees, shrubs and ground covers are either shorn too much to develop their naturally appealing forms, or not pruned severely enough to allow space for resulting new growth to mature and bloom like it should. Gardeners are notorious for shearing anything within reach. However, they are also notorious for allowing certain ground covers to get too deep and overgrown.

Trees that are short with multiple trunks when they first get planted are more likely than taller trees with single trunks to be shorn into nondescript shrubs. Olive, Japanese maple, tristania (laurina) and crape myrtle are commonly victims of this abuse. They are not only deprived of their form, but their grace and foliar appeal as well. Shorn crape myrtle may never be able to bloom.

Oleander, bottlebrush, arborvitae and various pittosporums that make nice informal screens in their natural forms are likewise very often shorn inappropriately and needlessly into all sorts of odd geometric shapes. Fortunately, pittosporums tend to make excellent formally shorn hedges as well as informal screens. Yet, when shorn without a plan, they more often develop into herds of noncontinuous geometric shapes. Oleander and bottlebrush, like crape myrtle, may never bloom if shorn too frequently.

Ground cover more often has the opposite problem. It does not get mown enough, or otherwise pruned down to stay shallow. This may not be a problem in most of the space covered by ground cover, but does make for hedge-like edges where the ground cover meets walkways, with all the problems of improperly shorn hedges. These edges can be softened if sloped inward and rounded off on top. However, lantana, star jasmine, acacia redolens and the ground cover forms of ceanothus do not bloom on these shorn edges unless the shearing procedure gets done at the right time to allow for enough new growth to mature in time for the blooming season.

There is certainly nothing wrong with properly planned and properly shorn formal hedges; but not everything needs to be shorn. Plants should be selected to be proportionate to their particular application without abusive shearing. Like the hair styles of the 1980s, the assets of each particular plant should be exploited instead of destroyed.


Shear Hedges Seasonably And Properly

Scheduling is important to hedging too.

There are rules to hedging. For example, hedges should be uniform and exclusive to just a single cultivar. A modern ‘Green Beauty’ boxwood will never conform within a hedge of more yellowish old fashioned boxwood. Hedges should also remain within confinement. It is important to shear them back from obtrusion into walkways and other usable spaces.

It is not as simple as it seems to be. That is why so few hedges get proper maintenance. Almost all occupy and therefore waste more space than they need. Most have wide tops that shade out narrower lower growth. Moreover, many plants that are not components of hedges all too commonly succumb to inappropriate shearing too. It is sheer shear abuse!

Even if done properly, only hedges and a few other plants are conducive to shearing and hedging. It is an aggressive procedure that compromises form, texture and bloom cycles of involved plants. For hedges, that is not a problem. They need not bloom, and adapt to a refined hedged form, which is more desirable than their natural shrubby form would be.

However, it is important to not unnecessarily shear plants that bloom, or provide intricate foliar texture or form. Shearing deprives rhododendron of young floral buds. It ruins foliar texture of Heavenly bamboo, and foliar form of Japanese maple. It is acceptable to shear boxwood only because it responds by generating such appealingly uniform foliar growth.

With proper scheduling, it is possible to shear only a few blooming plants without ruining all of their bloom. Aggressive shearing after the early bloom of oleander and bottlebrush leaves them with space to grow enough to bloom again during autumn. Without sufficient space to grow, they will require subsequent shearing, which will ruin subsequent bloom.

It is better to shear some of the simpler hedges, such as privet and boxwood, shortly after winter. They regenerate lush growth immediately afterward, and do not mind two or three annual shearings. The last shearing should be early enough to allow a bit of growth prior to autumn. Photinia generates appealingly bronzed new growth in response to shearing. Also, frequent shearing inhibits potentially undesirable bloom.

Shearing Can Not Fix Everything

Shearing enhances foliar density without bloom.

Mowers are for mowing lawns and shallow ground cover. Blowers are for blowing debris from pavement, decking and other flat surfaces. The names of these tools suggest these particular functions. Those of us who use such tools tend to be aware of their limitations. Why are simple concepts of shearing and the associated tools so difficult to understand? 

‘Mow, blow and go’ gardeners are not so bad if they simply mow, blow and go. They tend to the two most significant but also least pleasurable tasks in the garden, and then leave before causing problems. Most are also qualified to add bedding plants or shear hedges. However, some will shear anything that is within reach of their powered hedge trimmers.  

Shearing is for hedges or shrubbery that is strictly foliar. There are few exceptions. Such shearing should be performed properly, and only for the few plants that are conducive to it. The process promotes foliar density, but also generally inhibits bloom. For hedges that function as living fences in the background of more interesting plants, this is no problem.

Otherwise, shearing plants that are not conducive to it ruins appealing form, and inhibits or prevents appealing bloom. Privet and photinia perform well as shorn hedges because their dense evergreen foliage is their primary asset. Their bloom is actually undesirable. Their natural forms are unremarkable, but their shorn forms can be remarkably practical.

Frequent or untimely shearing prevents lemon bottlebrush and oleander from blooming. However, shearing immediately after a bloom phase stimulates new growth to bloom for a subsequent phase. New growth only needs an opportunity to mature and bloom before removal. Such potentially blooming stems need extra space to extend prior to blooming.

As practical as it is for hedges, shearing ruins the foliar texture of other plants. Heavenly bamboo is worthlessly shabby without its naturally intricate foliar texture. Juniper retains good color, but becomes boringly plain. Rhododendron and hibiscus become disfigured and can not bloom. Each of these plants and all others are discriminating about pruning. Few are agreeable to shearing.

There Are Rules To Hedging

Few plants are conducive to shearing

All the wrong plants get shorn. Mow, blow and go gardeners are known for shearing everything that they can reach into creepy and unnaturally geometric shapes, usually flared out at the top, and bulging obtrusively into otherwise usable space. Yet, functional formally shorn hedges are passe and almost never shorn properly.

First of all, a formal hedge should be uniform, which means that all the plants that comprise it should be the same, and planted at the same distance from each other. Any plants within a formal hedge that die should be replaced with the same plant. A single English boxwood plant added to a Japanese boxwood hedge will always stand out with a different shade of green and growth pattern. Seedlings of other plants that grow up into a hedge should be removed before they become part of it.

Secondly, a formal hedge should be contained within defined boundaries. It should get neither too tall, nor too deep (from front to back). A fat hedge wastes space. There is no excuse for a hedge to encroach obtrusively over walkways, driveways or patios.

The vertical faces of a hedge should be completely vertical or slope very slightly inward at the top, but should certainly not slope outward to shade lower growth. A slight inward slope is more important on a northern face of plants that are sensitive to shade.

Hand pruning hedges (with hand shears) produces the best finish, but takes quite a bit of time for big hedges. Shearing with typical hedge shears cuts leaves as well as stems, so can cause foliage with large leaves to look a bit tattered for a while. Hedges that grow fast may need to be shorn twice or more annually. Some hedges can get shorn back aggressively once annually, and then allowed to fluff out evenly through the rest of the year. Bottlebrush and escallonia hedges can bloom nicely and evenly if shorn only once annually.

Glossy and wax leaf privet are among the most traditional of formal hedges. Glossy privet can get quite tall, but wax leaf privet actually has glossier foliage. Photinia and shiny xylosma have a bit more color, but want a bit more space (from front to back). Boxwoods make very nice small hedges. Pittosporums are available in various shapes and sizes. Pittosporum eugenioides gets quite tall, and can be kept quite lean. Pittosporum tobira is shorter and wider.

Hedges – Living In The Background

90918thumbPretty soon, as autumn weather starts to get cooler, some deciduous plants will develop brilliant color before defoliating for their winter dormancy. Throughout the rest of the year, evergreen plants with gold, silver, bronze, bluish, purplish, reddish or variegated foliage are more colorful than common green foliage is. A few deciduous plants with colored foliage turn different colors in autumn.

Such colorful foliage is generally appealing in the garden. However, there are reasons why not all plants in the garden are so colorful. There really is the potential for too much of a good thing. If all foliage was always colorful, landscapes would look cluttered. Flowers would not be so prominent. There are many situations for which plain and simple evergreen foliage is likely the best choice.

That is why simple evergreen hedges of the various species and cultivars of pittosporum, privet, holly, arborvitae and laurel are still so popular. Some are formally shorn. Where space is sufficient, others are informal screens in which the shrubbery is more or less allowed to assume its natural form and size. The various boxwoods are useful for smaller evergreen and formally shorn hedges.

Most contiguous hedges and screens are intended to separate spaces or obscure fences or buildings. Some sporadic sorts might only expected to disrupt the expansiveness of large buildings or partially deflect prevalent breezes. What they have in common, is that they are in the background. Some are behind or next to lawns, patios or decks. Others are behind more prominent plants.

Shearing hedges that are adjacent to lawns, patios and decks is of course much easier than shearing those that are behind other plants. Screens or hedges behind rose gardens, dahlias, flower beds, or anything that might be damaged by the process of shearing a hedge, should be of the sort that do not need to be shorn regularly. Nor should they be so colorful that they steal the show.

If possible, maintenance of hedges should be scheduled to coincide with the off season of plants in their foreground.

Horridculture – Instant Hedge

P90220Back when horticulture was still respected, a very long time ago, dense shrubbery with finely textured foliage, such as Japanese boxwood, could be purchased already shorn into cubes that only needed to be installed in a closely set row to become an ‘instant hedge’. For some small hedges composed of small plants that recovered efficiently from transplant, it actually worked reasonably well, even if they did not look so great at first. It also worked for a few larger shrubs that happened to transplant very easily, such as glossy privet. Tall arborvitaes happen to work exceptionally well as instant hedges, although the best spacing for them leaves temporary gaps in between.
However, most of the best of the bigger shrubbery should not be planted as instant hedges. The taller specie of Pittosporum get too distressed from transplants when mature, so should instead be planted while small, and allowed to grow into a hedge. Larger and much more expensive shrubs, take a few years to recover from transplant, and some recover much slower than others, compromising the conformity of the hedge as it develops.
That being said, I am not certain what to say about this instant hedge. The individual plants are much too close to each other, probably because someone wanted instant coverage, but perhaps because the so-called ‘gardener’ could charge more for installing more plants. I seriously doubt that the so-called ‘gardener’ will be able to contain these junipers, which will want to get much taller and wider than their confined space will allow. Even if the hedge bulks out just a slight bit beyond the curb, it will shade out the lower foliage more than it already is. I actually expect the junipers to grow well out into the driveway within only a few years, as they compete for space. If they get big enough, they can break the curb and asphalt pavement. It annoys me mostly because I like Skyrocket juniper so much, that I hate to see it abused like this.
Yet, It could work. As unlikely as it seems, there is a very slight possibility that the so-called ‘gardeners’ may be more qualified than I give them credit for. (Or they might be replaces with such. This is after all, the backside of the same landscape that is inhabited by the crepe myrtle featured last Wednesday.) After all, someone seemed to have enough sense to select #5 (5 gallon) plants instead of #15 (15 gallon) plants that would not be doing so well now. If the top of the hedge is kept down to prevent the junipers from growing as trees, and the facade of the hedge is kept contained to within about a foot and half of the wall behind it, lower growth will regenerate and get enough sunlight to not get shaded out. It will take serious commitment, and a specialized combination of regular shearing and selective pruning to limit congestion, but this hedge just might work.

Horridculture – Satellite Dish


Satellite dishes, tater tots, fish sticks, soldiers, flat tops, gobstoppers, corks, oil tanks and trip hazards are just some of the many but less objectionable names that my colleague down south and I have developed for what should be good shrubbery, trees, vines or whatever that so-called gardeners got to with their hedge shears. Tater tots are usually Heavenly bamboo shorn into stout cylinders. Fish sticks are the same, but taller, narrower, and often composed of Podocarpus macrophyllus. Corks are commonly breath of Heaven, but could be just about anything shorn to be somewhat cylindrical, but narrower down low, and wider on top. Trip hazards are ground cover plants like creeping California lilac or creeping cotoneaster, shorn into absurd low hedges next to sidewalks. Gobstoppers could be just about anything, but tend to hang over the curbs in parking lots, ready to impale a radiator grill with a gnarly stub. You can use your imagination for soldiers, flat tops and oil tanks. You probably can not conceive anything more absurd than what my colleague and I see on our job sites.

‘Garage sales’ are probably the worst. They are a variety of plants that were probably intended to function as a practical landscape, but instead got shorn collectively into a large thicket of mixed foliage that rarely gets the chance to bloom. Bougainvillea, New Zealand flax, jade plant, pampas grass, wisteria, fruit trees and even the occasional century plant; anything goes! If the so-called gardeners can reach it, they will shear it.

The original satellite dish was a carob tree in Westchester. I first saw it in the early 1990s, when some homes that had a bit of space to spare were still outfitted with huge parabolic satellite dishes, before the much smaller ones that can be mounted on roofs were invented. This tree had a normal trunk that went up into a remarkably flat ceiling under which no foliage was allowed to hang. This ceiling was only about seven feet above the lawn below. Above that, there was a remarkably symmetrical but low dome of very tightly shorn foliage that looked something like a downward facing satellite dish. This dome was perhaps twenty feet wide, but less than four feet from top to bottom. So, with seven feet of clearance above the lawn, the entire tree was no more than twelve feet tall, barely higher than the eaves of the home behind it. I really wish I had a picture to share. Who puts so much work into ruining a tree?! Maintaining it properly would have been much less effort.

Earlier, we discussed renovating overgrown shrubbery as small trees. . The satellite dish was the exact opposite of such useful procedures. What is the point of planting trees and then not allowing them to develop as anything more than abused shrubbery?

The pair of satellite dishes in the picture above are Japanese maples. Their canopies are about the same depth as that of the carob tree in Westchester, but are only about half as broad. What is the point of planting Japanese maples if they are not allowed to look like Japanese maples? They look ridiculous. What is worse is that someone puts significant effort into making them look so ridiculous. They would be so much prettier if pruned only very rarely, and only for clearance above the driveway and away from the building behind. Such pruning would have been less work than shearing these disgraced trees just once.

Even more effort goes into humiliating the plants in the picture below. The fish stick to the upper right is a wisteria vine that is not allowed to bloom or climb onto the trellis that was built for it (which is not visible in the picture). The trip hazard to the lower left is some sort of lavender that is not allowed to spread out over the bare soil as it was intended to do. The cork in the middle is a New Zealand tea tree that can never develop the gracefully irregular canopy and sculptural trunks that it would be pleased to display. It is just a cork.


Horridculture – Fat Hedges


This is the first article within the designated ‘rant’ format, that will continue each Wednesday. Articles for the other six days of the week will be more cheerful, or at least less objectionable. These articles may not always be rants, so might alternatively include discussions of particular fad, trends, gimmicks and so on. Perhaps some topics will remain just that; discussions in which the advantages and disadvantages of a particular subject are compared. Categories may develop, so besides ‘Horriduclture’, there could be a category for discussions of fads, for example. This is a new format for me, so I will keep it open to modification, and see how it goes.

Fat hedges are one of my serious peeves!

Hedges done properly are very useful landscape features, that provide privacy, obscure undesirable views, muffle outside sound or simply divide a large garden space into smaller garden rooms. Landscape designers know how to use them, and are good at planning their locations and orientations, as well as designating the plant material to be used for particular hedges. Some informal hedges or screens are outside of useful space, where they have plenty of room to grow plump and wild without becoming obtrusive. Formal hedges are those that require shearing for confinement within limited space.

Fat hedges are those that are designed to be contained, typically by formal shearing, but are instead allowed to encroach into the usable space within the landscape that they are designed to enclose. They can be a serious problem in confined garden space, and sometimes occupy most of the space themselves.

Seriously, they are very often several feet deep (from front to rear). Fat hedges on either side of a small garden room that is only about twelve feet wide can easily occupy more than half of the area. Think about it. If each hedge is just three feet deep, and there are two hedges, that means that six feet of the width of the twelve foot wide space is occupied by fat hedge! That is half of the area available! Some fat hedges are even deeper! A fat hedge does nothing more than a properly maintained hedge. Really, a three foot hedge accomplishes no more than the same sort of hedge that is only one foot deep. The interior is only bare twigs.

Fat hedges are mostly the result of inept gardeners who allow the hedges to gain a bit more width with each shearing, without ever renovating overgrown hedges. To make matters worse, they allow the tops of the hedges to get wider, which shades out lower foliage, which becomes sparse. Then the fat hedge becomes a top heavy hedge, leaning into usable space where it should be leaning slightly away. Ends of top heavy hedges often protrude a bit more than the sides of the hedges. If these hedges flank a driveway or walkway that is perpendicular to the sidewalk or a patio, the distended end is particularly obnoxious.

In the picture above, the low hedge seems to be well maintained. If it is a fat hedge, it is in a situation where it is not really crowding much. However, notice the width of the sidewalk. It is quite broad. Then there is a significant constriction where the hedge protrudes over the sidewalk. What is the point of so much concrete and such a wide sidewalk if almost a quarter of the width of it is overwhelmed by vegetation? It is like four lanes of freeway that merge into three, only to merge back into four.

Cherry Laurel

80530There is a reason why the most popular specie for frequently shorn formal hedges have small leaves and finely textured foliage. Technically, a formal hedge of cherry laurel, Prunus laurocerasus, can be shorn as well, but should be shorn only once or twice annually, and then allowed to fluff back out. Otherwise, the big leaves get shredded as quickly as they recover from previous shearing.

If pruned more frequently, hand pruning works best, and is not as tedious as it sounds. Informal pruning is even easier, and is done primarily to prevent hedges from getting to deep (from front to back), and to prevent individual shrubs from dominating or subordinating. Pruning also eliminates most of the abundant summer bloom of upright trusses of thirty or so tiny creamy white flowers.

Cherry laurel is densely foliated and quite stout, even without shearing or pruning, and can eventually but rarely get thirty feet tall! The glossy evergreen leaves are about three inches long. There happens to be a few cultivars, including one that is variegated with light yellow, and others that are compact dwarfs. (Prunus caroliniana is different species that is also known as cherry laurel.)

Hedges Are Like Green Fences

80502thumbHedges are a complicated topic! Like lawns, they are among the more functional features of a landscape. They can be used to provide privacy within, obscure unwanted views beyond, or merely to separate a large landscape into cozier or more functional spaces. Except for hedges that are grown for spring flowers or autumn color, most hedges are evergreen with finely textured foliage.

Informal screens, which might also be know simply as informal hedges, can function like hedges, but are a bit different. They are not regularly shorn, so do not need such finely textured foliage. They are either compact plants that stay proportionate to their particular situations, or are grown outside of a refined landscape, where they have plenty of space to grow wild to their natural size.

Although they do the work of fences and walls, hedges do not substitute for them. Fences are relatively ‘low maintenance’. Hedges are quite ‘high maintenance’. They need everything that other plants need, as well as dutiful shearing. Espaliers, trellised vines or vines clinging to fences or walls are also very different, with their own intense maintenance requirements and innate problems.

Most hedges were shorn late last summer or early autumn, but have not done much since then. They should have been shorn early enough for new growth to toughen up a bit to not look shabby or sparse through winter. Now that hedges are growing again, they will need to be shorn again. If space allows, shearing of photinia hedges can be delayed until the red new foliage fades to green.

While hedges get shorn, any volunteer plants that have self sown into them must be removed. Different species of shrubs or vines that sneak in will ruin the symmetry. This is also very important when adding new shrubs to replace any that might be missing. Even different cultivars of the same species will exhibit different color and growth rates. The sides of hedges should be sloped slightly inward at the top to allow more sunlight to reach the bottom, and to compensate for faster upper growth.