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Hybrids Of The Botanical Nature

Fancy gladiolus are products of hybridization.

Botanical nomenclature has gotten sloppy. So has breeding. Hybrids of different species are now common. Their botanical names often lack proper species designation. Instead, their names include only their genus names with their variety or cultivar names. This can seem simpler. However, it complicates the simplicity of binomial botanical nomenclature.

Interspecific hybrids involved different species of the same genus. Therefore, any genus name is the same as that of both parents. An “X” precedes its species name to indicate it as an interspecific hybrid. Its species name is as new and unique as the new hybrid. Any cultivar or variety name follows its species name in single quotes. it is all quite sensible.

Intergeneric hybrids involved different genera. Therefore, an “X” precedes a genus name of an intergeneric hybrid to designate it as such. Its entire name is as new and unique as the hybrid. Like for all botanical names, both its genus and species names are italicized. This designates them as ‘Latin’ names. Variety and cultivar names lack such italicization.

Many hybrids are naturally sterile. Most that can produce viable seed are not true to type. In other words, their progeny is very different from them, and commonly of inferior quality. Most hybrids are therefore cultivars, or cultivated varieties. They are reliant on unnatural cultivation for perpetuation. However, some naturally perpetuate vegetatively, like canna.

Tree ivy, X Fatshedera lizei, is an example of an intergeneric hybrid. The “X” in its name precedes its genus name. London plane, Platanus X acerifolia, is an interspecific hybrid. The “X” precedes its species name. Platanus X acerifolia ‘Liberty’ is a cultivar of London plane. Its species name remains, which is proper with botanical nomenclature of hybrids.

Rhododendron and rose hybrids violate nomenclature rules because of their breeding. It is too extensive for their species to be identifiable. For them, the abbreviation “spp.” may substitute for a species name. It is for “species pluralis”, which means “multiple species”. Although it is Latin, it is not italicized. Nor are their more important cultivar names after it.

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Stick

‘Beurre d’Anjou’

Here it is. The stick! I paid $7.79 for it with delivery from San Leandro, and waited a few days for its arrival last Wednesday. Since then, it was processed into two scions and a cutting, each with two buds. The terminal bud of one of the scions is actually accompanied by a few smaller buds. The scions were grafted, and the cutting was plugged, last Thursday, less than a day after the Stick arrived. I am very pleased with the results, and hope to be even more pleased with their favorable performance in the future. Ultimately, the finished product will be at least one pear tree. More specifically, it will be a ‘Beurre d’Anjou’ pear tree, which is more often known as ‘d’Anjou’ or ‘Anjou’. It and ‘Seckel’ were the only two cultivars of pear that I wanted to acquire this winter. After obtaining scions for ‘Seckel’ pear from the Scion Exchange of the Monterey Bay Chapter of the California Rare Fruit Growers on the first of February, ‘Beurre d’Anjou’ remained elusive. Every pear tree that I could get scions from was either another cultivar, or not identifiable by cultivar. I really thought that the process would be simpler. I could have purchased a tree from bare root stock at a nursery, but that would have been comparable to cheating, and would have cost about $40. The well rooted quince understock for grafting was already here and waiting. I grew a few specimens of it from suckers of an established pear tree, and already used one for the previously acquired ‘Seckel’ scions. Because I was so confident that I would eventually acquire the only pear cultivar that I craved more than ‘Seckel’, I retained the biggest and best of this understock for these recently acquired scions of ‘Beurre d’Anjou’.

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Second White

How did this get in here?!

Lily of the Nile had previously been exclusively blue at work. Many from undoubtedly several different sources had been added to the landscapes for the past century or so, but, until recently, none were white. Even within a large and likely original colony, where genetic variability is evident among specimens that were added from different sources, or that grew from seed over the years, all bloomed monochromatically blue. I added the first white lily of the Nile only a few years ago. They are a significant herd of the same cultivar that I grew from only seven original pups that I acquired in the early 1990s. They are separate from the other lily of the Nile, in a neat row in front of the White Garden of el Catedral de Santa Clara de Los Gatos. They are not as fancy as they sound of course, and bloom with only a few flowers in the partial shade there, but they were supposedly the only white lily of the Nile. However, I recently found this other white lily of the Nile within the large and very established colony that provided many lily of the Nile for other landscapes. It could have grown from seed, and finally matured enough to bloom. I suspect that it merely reverted, as lily of the Nile sometimes does. I suppose that I should be pleased with it, but I am not so certain. It is almost intrusive, both to the exclusivity of the single white cultivar, and also to the exclusivity of the monochromatically blue colony. I have noticed within other old landscapes that, once one pup blooms white, others can follow its example. The same applies to a pup that blooms blue within a white colony. I may tag this particular pup for removal after bloom.

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Form Follows Function For Gardening

Star jasmine either climbs or trails.

Home gardens are components of the homes that they serve. They are the exterior of the interior. They are the environments in which homes exist. Some provide vegetables and fruits. Many provide flowers. Ideally, gardens enhance domestic experiences. Therefore, their design is as relevant as architecture. Accordingly, horticultural form follows function.

Gardens can be single open spaces or, like their associated homes, a few spaces. They benefit from features that function like those that define interior spaces. Lawns are floors. Trees are ceilings. Hedges and shrubbery are walls. Patios, decks and fences are static features. Vegetation, though, requires more discriminating selection for appropriate form.

Lawns seem to be the simplest of such functional vegetation to select. Form is not overly variable. Nevertheless, turf grass must be appropriate to its particular exposure. Some is more tolerant of partial shade than others. Some requires less water than others. Ground cover vegetation is more appropriate for many situations. Artificial turf might be an option.

Trees and shrubbery are much more diverse. Although they are the largest vegetation of a garden, some are quite small. They are evergreen or deciduous, and both have distinct advantages. While palms lack branches, other trees and shrubs develop sculptural form. Consequences for inappropriate selection of such significant vegetation can be serious.

Furthermore, different varieties of the same species can behave very differently. Junipers are practical shrubbery for some situations. However, some are prostrate ground covers. A few grow as small trees. Also, while some rosemaries are shrubbery, some are trailing. Selection of an inappropriate cultivar of an appropriate species is a rather common error.

A few species change form as they mature. With confinement, the trailing juvenile form of English ivy is a practical ground cover. However, as it encounters support, it becomes its vining adult form. This clinging growth ruins paint, and overwhelms trees and shrubbery. Star jasmine evolves from ground cover to twining vines even without changing its form.

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Cultivar Is A Cultivated Variety

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Most cultivars need to be cloned.

A plant ‘variety’ is a group within a species that exhibits distinguishing characteristics. A ‘cultivar’ is simply a cultivated variety. The first five letters of ‘cultivated’ merged with the first three letters of ‘variety’ to form the word ‘cultivar’. A variety should be self perpetuating to some degree, and may be naturally occurring. A cultivar perpetuates by unnatural means, and would go extinct otherwise.

Of course, the distinction between variety and cultivar is not always so obvious. Varieties of nasturtium were selected from plants that displayed desirable qualities. Seed of these varieties grows into plants that display the same qualities. However, without continued selection, some varieties eventually revert to a more feral state in only a few generation. They are not truly self perpetuating.

Most hybrid tomatoes are unable to perpetuate themselves naturally. Their seed is either not viable, or is very genetically variable. Genetically variable seed grows into plants that are very unlikely to produce fruit that is comparable to that which produced their own seed. Nonetheless, hybrid tomatoes grown from original (primary generation) seed are generally varieties rather than cultivars.

The distinction might be that they grow from seed. A plant that is cloned rather than grown from seed is a cultivar. Cloned plants can be grown from cutting, layering or grafting onto understock, but are genetically identical to the original. Some rare camellias grown now are genetically identical copies of original cultivars that were developed centuries ago. Their seed would not be the same.

Some cultivars developed from selective breeding. Others were random but appealingly distinctive plants in the wild or even in landscapes. Many originated as ‘sports’, which are mutant growths of otherwise normal plants. For example, some plants, on rare occasion, produce stems with variegated foliage. Cuttings taken from such variegated stems became popular variegated cultivars.

Seed from a variegated cultivar is very unlikely to produce more variegated plants.