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.

Cultivars Are Merely Cultivated Varieties

Cultivars are distinct within their species.

Nomenclature is simply the technique of naming. Botanically and horticulturally, it is also a precise method of classification. Large classifications divide into smaller and exclusive classifications, which likewise divide. Botanical families divide into many genera, which likewise divide into many species. Some species divide further into varieties or cultivars. 

For example, Schwedler maple is within the Sapindaceae family. This family divides into many genera including the maple genus of Acer. (Genera is plural of genus.) This genus divides into varied species, including the Norway maple species of platanoides. Norway maple divides into more cultivars, including ‘Schwedlerii’, which is the Schwedler maple. 

Therefore, the botanical name of the Schwedler maple is Acer platanoides ‘Schwedlerii’. Family names are omissible. Genus names justify capitalization. Species names do not. Both genus and species names appear in italics. (Incidentally, genera are more ‘genera’l than ‘speci’fic species.) Single quotation marks contain names of varieties and cultivars.

Varieties are, as their designation implies, variants of a species. Some are dwarf, like the dwarf pampas grass. Some bloom with atypical color, like the maroon Texas bluebonnet. Their variations are natural and at least somewhat inheritable. Cultivars are varieties that can not perpetuate naturally, so are reliant on cultivation. They are ‘cultiva’ted ‘var’ieties.

Some cultivars developed from breeding. Others are naturally occurring mutants that are desirable enough to perpetuate. Because their unique characteristics are not inheritable, perpetuation is artificial. Seed of cultivars that originated as mutants lacks any desirable mutation. Seed of extensively bred cultivars is genetically unstable, or may not be viable. 

Most cultivars therefore rely on cloning for perpetuation. Propagation by cutting, grafting, division, layering and tissue culture, generates genetically identical copies of an original. Although it is illegal to propagate patented cultivars for profit, most common cultivars are too old for patents. Many perennial cultivars, such as iris and canna, proliferate naturally. 

Six on Saturday: How It Should Be

Well, I can not argue that ‘everything is as it should be’. Turkeys serve more of a purpose than food, although I can not figure out what their other purpose is. Coleus are so delightfully colorful that those with more discerning taste than mine enjoy new and ‘improved’ cultivars. Many of those same people with discerning taste also enjoy Japanese maple too much to consider options. Both my blue and white lily of the Nile are still the best! Yes, but . . .

1. Turkey belongs in an oven, or perhaps in a freezer. She should not be doing this at the shops as I write. At least she is not somewhere else shredding flowers or pulling up irrigation emitters.

2. Coleus reminds me why I dislike most modern cultivars. I would find this to be more appealing if I did not know what this is, or if I did not know the potential of good old fashioned coleus.

3. Coleus should look like this, which is more similar to how it looked when it was popular as a houseplant decades ago. My kindergarten teacher grew one like this in our classroom back then.

4. Vine maple should be more popular than Japanese maple is. I realize that Japanese maple is much more interesting and diverse. However, now that it is very popular, it is almost mundane.

5. Lily of the Nile should also bloom red, for a red white and blue bloom on Independence Day. There are plenty that bloom blue here. The first that will bloom white were added a month ago.

6. Rhody should cooperate when I need his help with an illustration. I needed a picture of mulch. I had visions of a stylish model in a Halston dress, leaning on a fender of a new 1972 Electra.

This is the link for Six on Saturday, for anyone else who would like to participate:

Cultivars Of California Native Plants

Some natives belong in the wild.

Native plants are obviously happy with local climates and soils. Otherwise, they would not be native. They had been living here long before the first landscapes. They survived without irrigation, fertilizer or any maintenance. Regional varieties adapted to regional environmental conditions. Some of such varieties became cultivars that are now familiar.
A variety is, more or less, a naturally occurring variant. Unnatural selection and breeding produced some varieties. Generally, varieties are genetically stable enough to replicate for at least a few generations. A cultivar is a cultivated variety. It is unable to replicate by natural processes, so propagates by cloning. All clones are genetically identical copies.
Most cultivars grow from cuttings. Some cultivars of exotic (nonnative) plants are grafts. (Not many natives are conducive to grafting.) Regardless of technique, propagation of all cultivars is vegetative (without seed). Seed of some cultivars can produce plants that are similar to the parents, but not indistinguishable. Some will likely be completely different.
Honestly, most native plants are not as appealing in home gardens as their cultivars are. Some are desert or chaparral plants, which can get scraggly through summer. Some are sparsely foliated with irregular branch structure. Like the majority of exotic plants, several native plants benefited from some degree of refinement. It is a fair aesthetic compromise.
This is partly why landscapes of native plants look nothing like forests or unlandscaped areas. The dense and strictly conical form of ‘Soquel’ redwood is very different from that of wild trees. ‘Carmel Creeper’ ceanothus is greener and more densely foliated than wild counterparts. ‘Ken Taylor’ flannel bush is likewise unnaturally dense, low and mounding.
The other primary reason that landscapes of native plants are so different from the wild is that they typically include species from other regions. Some of the penstemons that are popular as native plants throughout California are actually only native to the Siskiyous. Limiting landscapes to true regional natives would produce very different results.

Juniper Turns A New Leaf

Hollywood juniper was formerly overly popular.

Juniperus, which is the entire genus of juniper, had been languishing in a bad reputation for too long. The problem likely began nearly three quarters of a century ago. More people than ever were enjoying leisurely suburban gardening. Many appreciated the resiliency of juniper cultivars. At that time, a few species of juniper were gaining popularity. Evolving cultivars sustained new demand.

Unfortunately, these modern and once distinctive cultivars of juniper eventually became passe and too common. As practical and resilient as they truly are, they collectively shared the stigma of a minority that were problematic. Their problems were disproportionately evident merely because of their commonness. Many matured at the same time, so developed problems at the same time.

Realistically though, the majority of the garden varieties of juniper that grew during that time were quite practical. Those that started in the 1950s, but developed problems in the 1990s, performed satisfactorily for four decades. Not many other types of plants perform as reliably for as long. Many problems resulted from selection of cultivars that were inappropriate for particular applications.

Although all junipers are evergreen foliar plants that provide no obvious bloom, they are remarkably diverse. The most popular sorts are low and dense shrubbery. Others are lower and sprawling ground cover. Some are small trees. A few species grow more than thirty feet tall! Branch structure is mostly densely compact, but can be sculpturally irregular, rigidly upright or gracefully arching.

Foliage is generally rich deep green. Some cultivars exhibit yellowish new foliage that fades to green through summer. A few are variegated with creamy white. Several popular cultivars are gray or bluish gray. Leaves of almost all popular cultivars are scale like. Some have needle like leaves. A few have both. Even without prominent bloom, a few cultivars produce appealing tiny berries.

It is time for the many cultivars of juniper to grow beyond their former bad reputation and turn a new scale or needle.

Curb Mongrel

P91208Fruit trees, with few exceptions, have been extensively bred to produce the quality of fruit that we expect from them. Some are consequently genetically unstable, or at least less genetically stable than their wild ancestors were. Even if they never mutate or try to revert to a more stable state, they are very unlikely to produce seed that can develop into genetically similar trees.

In other words, they are not ‘true-to-type’. Their seed might grow into trees that produce fruit that resembles that of one of their ancestors, or of a pollinating parent tree. It is impossible to predict what fruit will be like until it actually develops.

That may take a while. Some seed grown fruit trees start out with juvenile growth, and take a few years to mature enough to bloom and produce fruit. Some types of avocado trees grow tall and lanky for a few years before they bloom. Most citrus are fruitless and wickedly thorny through their juvenile phase.

Grafted fruit trees or those grown from cuttings are true-to-type because they are genetically identical clones of their single parents. Cuttings and scions (for grafting) are made from adult growth, so do not need to mature through a juvenile phase.

The unpredictability of genetic variability is the main reason fruit trees are not often grown intentionally from seed. Juvenility might be the second main reason. However, neither of these two reasons prevents curb mongrels from growing wherever their seed lands, which is often next to sidewalks and curbs where cores and pits get discarded.

Curb mongrels generally get removed and disposed of, just like any other weed. It would be more practical to plant a known cultivar of fruit into a situation where such a tree is actually desired. Every once in a while, a curb mongrel appears where it is allowed to stay, and eventually produces fruit that justifies its preservation.

Well, that was not what happened with this curb mongrel apple tree that appeared adjacent to a patio used for outdoor dining. It was not compatible with the landscape, so got removed before it was able to produce any fruit. It looks like it was grafted, but only because someone tried to cut it down without removing the stump two years ago.

The problem now is that it came up with enough roots to survive relocation. It is not so easy to dispose of a tree with such potential, even though there is no way to know what its potential is until it fruits. It will get planted into a private garden and pruned back accordingly. If we had planned for it to be relocated, the process would have been delayed until it was defoliated.

If the fruit is of inferior quality, the tree can be removed and discarded. At least we tried. Alternatively, a desirable cultivar can be grafted onto it. In a home garden, no one needs to know that it is not a known understock (rootstock) cultivar. The foliage resembles that of ‘Red Delicious’, which makes sense for seed that likely originated from a commonly discarded core.

Horridculture – “One Of These Things . . . “

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!

White Hydrangea

P90907KWhat ever happened to the formerly common white hydrangea? It used to one of the three standard types of hydrangea; and the other two were really variants of the same sorts of ‘pink or blue’ hydrangea that I wrote about in ‘Horridculture – True Colors‘. The few hydrangeas that are white nowadays are lacy, flat-topped, blushed . . . or anything but simple classic white.

This old fashioned simple white hydrangea is just as elegant now as it has always been. It is always white, without pretense of blue or pink. There is no point of giving it something it does not really need just to change its natural color (like those of us in the Santa Clara Valley do to make pink hydrangeas blue; or those of us in the Tualatin Valley do to make blue hydrangeas pink).

The bulky and almost spherically rounded form of this floral truss distinguishes this old fashioned type as a ‘mophead’ hydrangea. Nowadays, ‘lacecap’, ‘mountain’, ‘smooth’, ‘panicle’, ‘oakleaf’ and ‘climbing’ hydrangeas are the more popular types. There is certainly nothing wrong with contemporary types, but there is nothing wrong with the old fashioned ‘mophead’ types either.

When it is time to prune the hydrangeas this winter, we might take cuttings from this particular specimen, in order to grow a few copies of it. Pink and blue hydrangeas, which get fertilized accordingly (to maintain their desired colors), happen to suit the landscapes very nicely here, but a few more white hydrangeas would brighten the rich dark green of the forest splendidly.

Besides, the old fashioned simplicity and elegance of this old fashioned white mophead hydrangea seem to be more compatible with the old redwoods and other mature forest trees than the relative flashiness of modern cultivars that were popularized only in the past few decades.

Paris Daisy

P90608KNo, this is not a Paris daisy. It is a common euryops daisy, Euryops pectinatus. It is obviously related, but the flowers are bright yellow rather than clear white with yellow centers, and the foliage is darker green. It is more resilient, so became more common in landscapes as quickly as mow, blow and go ‘gardeners’ replaced real gardeners who actually know something of horticulture. There is certainly nothing wrong with it. It is just cliché.

The few remaining Paris daisies are fancier cultivars of the old fashioned traditional sort anyway. Some bloom pale pink. Some bloom pale yellow. Flowers might have fluffy centers of the same color. Foliage might be pale grayish green. Plants are more compact. The cultivar that most closely resembles the old Paris daisy has more profuse, but smaller flowers. The cultivars are all quite nice, but are not quite the same as what we remember.

The original Paris daisy, Chrysanthemum frutescens, which is now known as Argyranthemum frutescens, was the sort of flower you wore in your hair if you were going to San Francisco in the late 1960s, or according to my memory, in the very early 1970s. It looked just like the three plastic daisies in the upper right (or lower left) corner of those cool AstroTurf door mats that were so popular. Perhaps they were cliché for their time too.

Cuttings rooted in half pint mason jars on kitchen windowsills to replace older plants. Our mothers grew them in the garden, supposedly to repel the bad insects, and attract the good insects to eat the bad ones who did not take the hint. In that regard, Paris daisies were how young horticulturists learned about vegetative propagation and ‘integrated pest management’ (IPM). They were so familiar back then; but then disappeared by the 1990s.

Only recently, Brent, my colleague in the Los Angeles region who I so frequently mention (typically in a disparaging manner) found just two specimens at a nursery in Southern California, and promptly procured both. One if for his garden, and one is for mine!