Conformity Is No Simple Task

Patching bald spots within Iris moss with Scottish moss might look . . . odd.

A combination of modern horticultural apathy and too many choices was probably the demise of conformity in home gardens. Formal hedges or even informal screens of several of the same plants are nearly obsolete. Ironically, long and low barrier hedges and so called ‘orchards’ of identical trees planted in regimented rows or grid patterns have become common in large landscapes in public spaces.

Those of us who still crave formal hedges, paired trees or any such symmetry in our home gardens must be more careful with the selection of the plants that need to conform than would have been necessary decades ago when there was less variety to complicate things. It is just too easy to get different varieties of the same plant. Only plants with matching cultivar (cultivated variety) names will necessarily match. (Yet, on rare occasion, even these are inaccurate.) For example, ‘Emerald’ arborvitaes will match other ‘Emerald’ arborvitaes, but will not match ‘Green splendor’ arborvitae, no matter how they resemble each other in the nursery.

Plants that are identified by their characteristics instead of by cultivar name are riskier. Blue lily-of-the-Nile could be any one of many different cultivars with blue flowers. It is therefore best to obtain all lily-of-the-Nile for any matching group from the same group in the same nursery at the same time. What will be available next week may actually be a different variety with a different shade of blue and different foliar characteristics. Nurseries bring stock in from so many different growers.

Adding new plants to replace those that have died within established hedges or streets flanked with the same trees can be particularly difficult, especially if the old varieties are no longer available. The old fashioned yellowish Japanese boxwood that was so common for small hedges in the 1950’s has not been common in nurseries for several decades. Replacement plants are darker green. Some are even compact cultivars or different specie like English boxwood. When lined up and shorn together, they make ‘calico’ hedges.

Sunlight Is Becoming A Commodity

Sunlight has not changed. Architecture did.

Shade trees are no longer appreciated like they had been. Only half a century ago, they were important components of suburban landscapes. Big deciduous trees shaded broad lawns and sprawling roofs during the warmth of summer. They defoliated to let warming sunlight through during winter. Now, modern architecture would not accommodate them.

Sunlight has not changed. Human interaction with it has. Modern homes are significantly taller, so create bigger shadows. They are closer together, with less garden space that is not within their bigger shadows, or shadows of adjacent homes. Higher fences intended to compensate for the minimal proximity of adjacent homes contribute even more shade.

Gardening can be difficult within the limited space and abundant shade of modern home gardens. Small evergreen trees or big shrubs that obscure unwanted scenery above the fences can also obscure much of the sunlight that manages to get past the infrastructure. Substantial vegetation in neighboring gardens can get close enough to be influential too. 

The primary part of modern homes that is not excessively shaded is the roof, which is not used for gardening. Trees that are proportionate to modern home gardens are not much taller than associated modern roofs. Modern attics are fortunately insulated so efficiently that shade is not important. Besides, many modern homes are outfitted with solar panels. 

Walls and windows of modern homes are efficiently insulated as well. Warming sunlight during winter is therefore not as much of an advantage as it is for older homes, although it is appealing within sunnier homes. Ironically, the utility cables of many modern homes are subterranean, so will not interfere with trees that get too big for their confined spaces. 

Regardless of their functions within their landscapes, even small trees can develop roots that are sufficiently aggressive to displace pavement and deck suspensions, particularly since they are likely to be close to them where space is limited. Turf grass that is thin and wimpy because of insufficient sunlight is more susceptible to lumpiness of surface roots. Because of proximity, neighboring gardens must be considered too.

No Respect

Like last Saturday and Sunday, the post for today is recycled from more than three years ago. I will be doing quite a bit of this for at least the next month. This one complies with the ‘Horridculture’ meme for Wednesday.

via No Respect

Eucalypti Are Innately Drought Tolerant

Distinctive foliage provided by red ironbark.

Drought is nothing new here. There could be plenty of rain next winter and for years afterward; but eventually, there will be another series of dry winters, prompting rationing all over again. Landscapers and big box garden centers continue with business as usual. It is up to us to manage our gardens responsibly. Besides native plants, aloes, yuccas, junipers and eucalypti are four groups of formerly popular, drought tolerant plants that are worthy of more attention again.

Eucalypti had gotten a bad reputation even before they became popular the last time around. Tasmanian blue gum, Eucalyptus globulus, that was planted so extensively for wood pulp and timber throughout California, is a huge and extremely messy tree. Yet, it is still the most familiar of the eucalypti.

Garden varieties of eucalypti are much more docile. Even though they drop their evergreen foliage and hard seed capsules throughout the year, they do so on a smaller scale. The tall and elegant lemon gum constantly sheds strips of bark like the Tasmanian blue gum does, but does not get big enough to be too overwhelming.

Because they are so undemanding, and some are somewhat messy, eucalypti are best in unrefined parts of the landscape, and away from lawn. Their mess is no problem over ivy or iceplant. They are happiest where other trees might be unhappy. Generous watering actually inhibits root dispersion, and can cause vigorous but structurally deficient stem growth.

Eucalypti innately prefer to be planted while very young, even from four inch or one gallon (#1) pots. Larger (and more expensive) trees, such as boxed trees, take so long to get established that they get passed up by faster growing tiny (and less expensive) trees. Because they are sensitive to confinement, eucalypti are unfortunately rare in nurseries.

The online catalog of Annie’s Annuals and Perennials, which is famous for excellently weird and undemanding plants, features lemon flowered mallee, red capped gum, silver princess gum, bell fruited mallee and fuchsia gum, all in four inch pots. The bell fruited mallee and fuchsia gum are like large but airy shrubbery that do not get much taller than the eaves.

Horridculture – β€œOne Of These Things . . . β€œ

P91120Remember this from Sesame Street?

One of these things is not like the others
One of these things just doesn’t belong
Can you tell which thing is not like the others
By the time I finish my song?

Identifying a blue balloon as different from three red balloons might be construed as discriminatory, but was fun back before we went into kindergarten. So was selecting the bigger bowl of Big Bird’s birdseed from three small bowls; or the beanie from three pairs of sunglasses; or the letter from three numbers. It is not so fun now, when conformity to a landscape is important.

In the picture above, one of the four prominent trees in the foreground of the walkway and rail fence, excluding the obscured middle tree, is different from the others. They are all the same age. They are all sycamores. They are all happy and healthy. They were all supposed to conform to the landscape of native vegetation in the background. Which thing is not like the others?

The second tree from the left is a London plane, Platanus X acerifolia. The other trees, as well as the fifth middle tree and the sycamores in the background, are native California sycamores, Platanus racemosa. Not only is the London plane not native, but it is distinctly smaller and more symmetrical, with a conspicuously straighter trunk and relatively orangish autumn foliage.

The picture below shows the bark of London plane, with a trunk of a California sycamore in the background. The second picture shows how dissimilar the bark of the California sycamore is.P91120+P91120++

Individually, there is nothing wrong with the London plane. A few could have made a nice homogenous grove in the same spot, although they would never attain the grand scale expected of California sycamore. The problem is that the London plane is similar to, but not the same as, the California sycamores. It will always look like one of the California sycamores with problems.

A completely distinct tree would have been better. If it were a redwood or a magnolia, or anything that is not so similar to California sycamore, it would not be expected to conform to them.

I see it commonly. Himalayan birch get added to groves of European white birch, even though their trunks are whiter and straighter, and their canopies are much more upright. Taller and leaner Mexican fan palms get added to otherwise formal rows of California fan palms. The formality of rows of tall and slim Lombardy poplars is similarly disrupted by fatter Theves poplar.

These bad matches are often honest mistakes. It is not easy to distinguish Theves poplar from Lombardy poplar; and Lombardy poplar is rarely available. Sometimes, so-called ‘gardeners’ or ‘landscapers’ simply do not care. An ‘Aptos Blue’ redwood was added to a grove that was exclusive to ‘Soquel’ in a nearby park, just because it was closest to the parking lot at the nursery.

So-called ‘landscapers’ sometimes ‘sub’, or substitute, a commonly available cultivar or species for something that was specified by a landscape design, but is not so readily available. It often works out just fine. However, I once inspected a landscape in which a ground cover cultivar of cotoneaster was subbed with Cotoneaster lacteus, which promptly grew higher than the eaves!

Horridculture – Parking Lot Islands

P80120kWhat a waste of space! What a waste of water! What a waste of time for the mow-blow-and-go ‘gardener’ who charges money to mow and edge it, but are too inept to suggest planting something that might actually be pretty, or shade the parking lot. There are a few of these between parking spaces marked for ‘compact’ cars, because it is cool to discriminate against full size cars that can not pull far enough forward to get out of the way.

Even between a Buick and a Chrysler, it is nothing to look at. It looks like something went seriously wrong with a grave site that was supposed to get a slab ‘over’ it (not ‘around’ it). It could be a Chia Pet litter box. There are much better spots to picnic at the park down the road. Whatever it is, it is not much better than the swales that are required in modern parking lots. It has potential to be a tripping hazard, but is not quite as dangerous.

I would make one of only two suggestions.

1 Pave over it. If there is not some building code that limits the area that can be paved, this might be thee most practical long term solution.

2. Landscape it responsibly. Yes; ‘responsibly’. Turf grass is just lame. Those trendy carpet roses that mow-blow-and-go ‘gardeners’ typically plant snag the clothing of those coming and going from the cars they park there. Since parking lots get warm, I would recommend shade trees with complaisant roots that are compatible with pavement. Such shade trees also should get tall enough to not obscure the signs on the buildings.

Parking lot islands contain some of the most deplorable landscapes. Trees commonly get hacked down below signs rather than pruned up and over them. Even if they get properly pruned with up-dos, their canopies must be carve around security lighting. Most problems result from negligent maintenance. Some problems result from design glitches. Realistically though, parking lot islands are very difficult to landscape well.

Boom! Zap! Wow! Bam! Zing!

P90630P90630+P90630++P90630+++P90630++++Batman and Robin were here!
. . . well, not quite. It is decoration for summer camp. We never know what we will find in the landscapes that we maintain here. Those who work at camp arrive before guests, so that they can get ready, and of course, to decorate. Guests only started to arrive two weeks ago. It makes our work more interesting, as we try to work around the traffic and events, but it is SO gratifying to see so many guests enjoy the facilities that we maintain!
Those who work at camp enjoy being here too. It is obvious in all the work they put into preparation. It gets pretty wild and colorful, as I was reminded when I found what had been done in a grove of coast live oak just outside of one of the main auditoriums. Last year, I pruned and groomed the trees to expose their naturally sculptural trunks. I thought they were rather exemplary; but apparently, there was some room for improvement.
There is more to the wardrobe of a well rounded tree than mere ‘trunks’. One might select stylish attire such as this. Really though, I am not certain if this tree is feeling ‘Absolutely Fabulous’ or totally embarrassed.P90630+++++
This one went for an old fashioned veil.P90630++++++
English ivy on the ground below the grove is wearing too much makeup.P90630+++++++
It is not really makeup of course. It is paint from this mysteriously hovering door . . . as if that somehow makes more sense. It was locked.P90630++++++++
This one is more my style, and it has a window. There is no need to open it to see what is outside . . . or inside.P90630+++++++++
If neither of those are good enough, there are plenty of others to choose from.P90630++++++++++


P90629KKIncandescent light bulbs were the standard form of electric lighting for more than a century after their invention. It took a while for fluorescent and halogen lamps to become popular; and by the time they did, high intensity discharge (HID) lamps had already become available. Nowadays, light emitting diode (LED) lamps seem to be replacing all sorts of electric lighting.
For a brief time in the late 1980s, high intensity lamps that were being used for large scale applications and street lamps became a fad for exterior household lighting. They worked nicely for driveways, so many of us believed that they would work just as nicely for night lighting of home gardens and patios.
By that time, most of us had realized that the sickly yellowish glare of the sodium vapor type of high intensity lamps that were so common as street lamps was not at all appealing around the home, and was downright unflattering for foliage and flowers in the garden. Mercury vapor high intensity lamps became more popular for such applications instead, even though their slightly bluish bright glare is no more inviting.
During this time, while the renowned landscape designer Brent Green and I were still studying horticulture at Cal Poly in San Luis Obispo, his father had a rather fancy mercury vapor lamp installed in his backyard.
Of course, Brent was furious! He had put so much effort into cultivating a remarkably inviting outdoor living space, only to have it illuminated at night like an industrial warehouse. When turned on, the lamp made a constant buzzing hum. It hung from a wall like a big glowing paper wasp nest. Brent referred to it at the ‘beehive’.
The quality of light produced by modern electrical light sources has fortunately improved since then. Nonetheless, contraptions such as this street lamp suspended on an otherwise exemplary ponderosa pine are not easy to warm up to.

Boulders In Modern Landscape Design

90703thumbIt is hard to say why boulders and sculptural stone are sometimes incorporated into American landscapes. A long time ago, boulders were only left in landscapes if they were to big and heavy to move out of the way or break apart. Early American landscapes were designed to express dominance over nature by replacing as much of it as possible with unnaturally organized landscapes.

Slowly through history, less refined and more relaxed landscapes became more tolerable, and then became popular as an expression of rebellion to earlier formality. Nowadays, most landscapes are inevitably informal, partly because so many believe that informality is more natural, and partly because few landscape designers will design anything else. Simplicity and symmetry are passe.

This informality allowed for the incorporation of various elements from various styles of landscaping, regardless of how incompatible some of such elements were with each other. Boulders and sculptural stone that had been traditional with many Asian styles of landscape design were added to American landscapes in rather nontraditional fashion. It has been a slow process of evolution.

Boulders are obviously nothing like viable and dynamic plant material, although they do contribute form, texture and color to a landscape. Designers might say that bigger and sculptural boulders add drama without even trying. In some situations, boulders are as functional as they are aesthetically appealing. They can obstruct unwanted traffic or hold back soil that is at a higher elevation.

If they need not conform to any of the various Asian landscape design traditions, there are not many rules for the use of boulders and sculptural stone. Exotic stone that might be incompatible to big open landscapes where exposed endemic stone is visible nearby, might be just fine in enclosed gardens where there is no reference for what is natural.

The standard rule of burying as much as two thirds of a boulder to make it seem as a natural outcropping is only valid if it is intended to look like a natural outcropping.

Utilitarian Landscape

P90505I am no designer. I am merely a horticulturist. I grow things, and I know how things should be grown in landscape situations.

My colleague Brent Green is a landscape designer, as well as a horticulturist. He knows how things should be grown in landscape situations too, but more importantly, he knows how to assemble the landscapes that they grow in. He creates the sort of landscapes that most people think that all horticulturists strive for. (A few pictures of his home garden can be found in a former article, as well as another similar article that it links to: .)

Brent and I have two completely different sets of standards for landscape design, to say the least. His ideal landscapes are very lush and inviting, with abundant color and fragrance. Mine are very simple and structured, with abundant fruits and vegetables. He strives to bring the ambiance of wild jungles into very urban settings. I try to instill formality and structure into the forests. Yet, we both agree that landscapes must be functional.

That means that landscapes must work for those using them, whatever they are using them for. Almost all of Brent’s clients use their landscapes as extensions of their homes, so want them to function as such.

I do not design landscapes, but I do happen to work in some. Most are in public spaces, and some are comparable to athletic fields. They function very differently from those in residential situations.

The unexpected way that these three small redwoods are functioning in this landscape was just too amusing to not get a picture of. I have no idea where all these wet suits came from, or why they are hung in this particularly prominent location, but it is the last thing I expected to encounter here.