Horticulturists are by nature, nonconforming. I happen to find it difficult to conform to what makes us nonconforming. Trends are fleeting. Old technology that has worked for decades or centuries is still best. Although I am not totally against chemicals, I find that almost all are unnecessary for responsible home gardening. Pruning is underappreciated, and fixes many problems.
Hybridization has produced unnaturally rich color.
Several species of iris are native to the West Coast of North America. Iris douglasiana is probably the most colorful species. Hybridization with the others improved its floral color range and other characteristics. Several of such hybrid cultivars collectively became the Pacific Coast hybrid iris. However, the various cultivars developed from various ancestry.
Most Pacific Coast hybrid iris are finishing their bloom about now. Some bloomed earlier, at the end of last winter. Their flowers can be various shades of blue, purple, red, orange, yellow or white. This includes lavender, burgundy, rust, rose, coral, gold or creamy white. Only green colors lack. Brown pods of sterile seed are visually unappealing after bloom.
Flowers are about three or four inches wide and stand about a foot tall. Individual flowers do not last long, but bloom in succession for quite a while. Grassy and dark green foliage develops low mounds that stay lower than bloom. Propagation is simple by division from large foliar mounds during autumn. Generous watering can cause rot and patchy growth.
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.
These six lack a theme. They are just random pictures of a few flowers that are blooming here and now.
1. Lavandula stoechas, Spanish lavender posed for this picture, which was not adequate for the gardening column, but is too pretty to delete without sharing here. It looks like it is about to fly away with those long wings. A bee posed with it for the gardening column.
2. (Hespero)Yucca whipplei, chaparral yucca is blooming again after blooming last year. This floral truss is about twelve feet tall, and still growing. Seed that it provided last year is now growing abundantly. It is the first species of Yucca that I met in the wild in 1985.
3. Scilla peruviana, Peruvian squill has been reliably perennial for about three years but has not grown much. Although the floral trusses are bigger than they were last year, they are no more numerous. Just nine remain in three groups of three, just as I planted them.
4. Rhododendron spp., like the bearded iris and cymbidium orchid, is of an unidentified cultivar. Many others are blooming now also. I refrained from posting six pictures of six different rhododendrons like I usually do though, because that can get a bit predictable.
5. Iris X germanica, bearded iris was difficult to take a good picture of at the time of day that I encountered it. Its pale color did not help. I am fond of this iris though, since I got it from Cedar Lodge at Kidder Creek, on the way to the Pacific Northwest two years ago.
6. Cymbidium spp., has been blooming very slowly. The buds appeared over winter, and have been extending since then, but only recently opened. I never liked this orchid much anyway. A white orchid that typically blooms so impressively here did nothing this year.
Orchid rockrose, as well as other rockrose, are remarkably resilient.
Out in the most remote islands in the vast parking lots of Westgate Mall, the three inch wide, bright pink flowers of orchid rockrose, Cistus X purpureus, defy the harsh exposure and sun baked soil. They begin to bloom somewhat abundantly about now after winter rains, and continue until the beginning of summer. Sporadic flowers can occasionally bloom out of season. The center of each flower looks like a starfish wearing a fuzzy sweater, because each of the five petals has a brownish red spot at the base, surrounding the bright yellow stamens.
Mature orchid rockrose plants are typically less than four feet tall and broad, with somewhat grayish green, aromatic foliage. Individual leaves are about one or two inches long. Older stems can be pruned out as they start to deteriorate and drop leaves, in order to promote new growth that lasts longer. Otherwise, plants look tired after a few years, and eventually die out. Orchid rockrose does not want much water once established, and can only tolerate frequent watering with good drainage.
Even native manzanitas, which really are drought tolerant, need water until they disperse their roots.
Nearly every landscaper and gardener brags about using plants that do not need much water. Buzz words like ‘drought tolerant’, ‘native’, ‘sustainable’ and ‘xeriscape’ have become all too common, even though few actually spell ‘xeriscape’ properly. (It is NOT ‘zeroscape’!) Unfortunately though, most gardeners water so frequently and generously that drought tolerant and native plants are less sustainable than plants that want more water.
The difficulty is that drought tolerant plants generally need rather regular watering immediately after planting, while they are still dispersing their roots, but then want to dry out between watering once they are established. Otherwise, they are very susceptible to rot if the soil is constantly moist. Most drought tolerant plants should therefore not be mixed with plants or lawns that want regular watering.
Trees like incense cedar, beefwood, carob, silk oak, olive, California pepper tree and some eucalyptus, pine and oak can be nice shade trees in lawns that are not watered too much, but do not live as long as they would with less water. (Although many are messy in lawns anyway; and carob smells bad when it blooms.) California laurel, African sumac, Australian willow, strawberry tree and most acacia and cypress are less tolerant of lawn irrigation.
Eucalyptus, pine, oak and acacia have sensitive roots, so do better if planted while young instead of as larger specimens. For example, #5 (5 gallon) red ironbark eucalyptus get established faster and grow larger than 24” boxed red ironbark eucalyptus installed at the same time.
Bottlebrush, oleander, cotoneaster, hop bush, firethorn, grevillea, some types of wild lilac and all sorts of juniper can be happy with or without regular watering. Manzanita, coyote brush, rockrose, flannel bush and western redbud really want to dry out between watering. Like many plants from arid climates, wild lilac, coyote brush, rockrose, flannel bush and western redbud are naturally relatively short lived. Western redbud fortunately has an efficient technique of producing an abundance of seed and replacing itself with new seedlings before if finishes.
Lily-of-the-Nile is one of the most useful perennials, and can survive with annual rainfall or nearly saturated conditions. New Zealand flax is nearly as adaptable, but is more susceptible to rot if watered too much. Rosemary and several iceplants are nice ground covers with or without regular watering.
The various yuccas, aloes, agaves and their other relatives are some of the most practical perennials for arid climates, and many tolerate somewhat generous watering if necessary. However, most agaves and yuccas have nasty sharp leaves; and some agaves get too big to keep at a safe distance. Also, their bold personalities are not adaptable to every garden style.
Only four species of Iris are native here. The problem with identifying them is that three of them can be visually similar. Only Iris douglasiana is reliably and distinctively blue. Iris longipetala and Iris macrosiphon are generally pale blue, but can be as pale white with pale yellow veins as Iris fernaldii. Without keying it out, I can only guess that this particular iris is Iris fernaldii. The others seem to develop slightly larger and denser herds with slightly more upright foliage. Iris fernaldii develops relatively smaller herds and more relaxed foliage that does not stand as upright. Even what seems to be large herds are typically groups of smaller herds. Their flowers can lay almost on the ground. they shrivel too soon after cutting to work well as cut flowers. Nonetheless, they are a delightful native wildflower that is blooming as freely as it can where it grows wild. I really should relocate those that grow where they are not wanted, rather than discard them with other weeds. They might compete with weeds and other less visually appealing naturalized vegetation within areas that are not landscaped. Actually, they might be appropriate for a few areas that are casually landscaped.
English lavender is likely the most common of this genus, with the most cultivars. French lavender is the primary culinary species. Spanish lavender, Lavandula stoechas, should likely be more popular than it is. All lavenders live for only a few years. Spanish lavender is more likely to self sow to replace itself, though. It can naturalize in favorable situations.
Spanish lavender is an evergreen shrub of irregular form, that grows as tall as three feet. Its finely textured foliage is grayish or drab green. Individual leaves are quite narrow and only about half an inch to an inch and a half long. Roots are not finicky about soil, but are likely to rot if irrigation is generous. Spanish lavender prefers warm and sunny exposure.
Bloom begins as soon as weather warms in spring and continues into summer. Sparsely sporadic bloom can continue until autumn. Dense floral spikes stand several inches over their foliage, on bare stems. They would not be very colorful if not for their few long upper bracts. Bloom is typically lavender, but may be bluish lavender, pink or very rarely white. It delights bees.
Floral fragrance attracts insect pollinators. Foliar aroma repels insect pathogens. It might repel other herbivores also. For organisms that lack olfactory perception, plants certainly make productive use of it. Fragrant flowers are as attractive in home gardens as they are to pollinators in the wild. However, aromatic foliage has the opposite of intended effects.
In other words, aromatic foliage is popular within home gardens because of its aroma. Its effort to be repulsive to some insects and herbivores makes it attractive to people. Some aromatic foliage has culinary or herbal application. Actually, almost all herbs are notably aromatic, with corresponding flavors. Mint, chive, thyme and sage are popular examples.
Window boxes became popular in ancient European towns because of aromatic foliage. Where garden space was scarce, they were convenient planter boxes for growing herbs. Also, prior to window screens, they sustained aromatic foliage that repelled mosquitoes. Trailing rosemary, ivy geranium and nasturtium are still very traditional accompaniments.
Rosemary has both culinary and aesthetic application. Culinary cultivars exhibit the best flavor. Landscape cultivars are either trailing or more densely shrubby. Some cultivars of fennel are similarly better for either culinary or landscape application. Bronze fennel has become popular for both. Varied lavenders are more popular as home garden shrubbery.
Native bay is very aromatic when its foliage is disturbed, but is not culinary bay. It is a big and obtrusive tree that is proportionate only to large landscapes. Culinary bay is another smaller species that is more proportionate to home gardens. Also, it has a distinct aroma. Incense cedar is another very aromatic native tree, but is quite rare within home gardens.
Most aromatic foliage can not exude its aroma like fragrant flowers exude their fragrance. Most does so only when disturbed. Some, such as that of many conifers and eucalypti, is beyond reach. It is therefore easy to dismiss within some landscapes. Lavender, lantana, diosma, rockrose and salvia stay within reach. Warmth and humidity amplify their aroma.