The once traditional Aeonium arboreum, with round, dense rosettes of slightly serrate, olive green leaves has become less popular than its more colorful varieties that have become more available over the years. ‘Atropurpureum’ has rich purplish brown foliage. ‘Zwartkop’ is even darker and stays more compact. Long and sometimes unkempt clusters of tiny yellow flowers that bloom in spring or summer are not much to look at against green foliage, but contrast nicely against dark foliage. Larger plants can get to three feet tall and wide, with foliar rosettes wider than six inches.
Like many succulents, Aeonium arboreum is so easy to propagate from cuttings, that small pieces that need to be pruned from established plants can be plugged into the garden wherever more of the same plants are desired. New cuttings like to be watered until they develop roots. Established plants are a bit happier with occasional watering, but can survive neglect just fine. After all, they are native to similar climates in the Mediterranean and northern Africa.
This is not a new problem, but it is infuriating nonetheless. ‘Cleopatra’ canna expressed symptoms of at least one virus about two years ago. A few other nearby cannas expressed similar symptoms shortly afterward. ‘Australia’ canna is particularly expressive of foliar streaking caused by virus. Isolation and disposal of obviously infected specimens seems to have prevented dispersion of the virus or viruses; but I really am uncertain. Three cultivars of Canna musifolia have suspiciously avoided any infection from adjacent infected cultivars. I can not help but wonder if they are actually infected but merely asymptomatic, and possibly able to transmit viruses to cultivars that are more expressive of symptoms. The canna in this picture is an important cultivar because it is one of only two remaining original cultivars that could have inhabited the landscapes here since about 1968. Because of gophers, very little of it remain, and some of what remains succumbed to virus already. I am quite protective of these few specimens that have not been infected, but would also like them to be able to inhabit the landscapes with the questionable Canna musifolia cultivars. For now, I must wait until they proliferate enough for some to be expendable.
Contrary to its silly name, sneezeweed, Helenium autumnale, does not cause sneezing. Its flowers produce heavy pollen that relies more on pollinators for dispersion than wind. Its vibrant yellow, orange or red floral color attracts all sorts of bees, butterflies and such. Bloom may begin as early as the middle of summer, or continue as late as early autumn.
Sneezeweed is a perennial like black eyed Susan, but with a somewhat shrubbier form. It can grow three or four feet tall without growing any wider than two or three feet. Foliage has a rather fine texture with lanceolate and somewhat serrate leaves. Individual flowers are about two or three inches wide, and delightfully abundant. They are nice cut flowers.
Sneezeweed may self sow, but some cultivars are not true to type. For them, division is a more reliable method of propagation. ‘Pumilum Magnificum’ provides vivid yellow bloom. ‘Chippersfield Orange’ provides vivid orange and yellow flowers. ‘Kupfersprudel’ blooms with a bit more yellow than orange. ‘Bruno’ blooms with deeply rich ruddy brown flowers. ‘Butterpat’ provides rich golden bloom. Several cultivars are compact.
Bear’s breech can be a bit too sustainable, and difficult to get rid of.
Like some other Victorian perennials that are still happy after a century, bear’s breech, Acanthus mollis, can get to be too much of a good thing. It can become invasive where not contained. Once established, it is difficult to eradicate. The bold coarse foliage looks great while the weather is favorable, but then dies back after bloom when summer weather gets warm, leaving obvious voids where other plants were crowded out.
The good news is that bear’s breech does not require much attention at all. It is very easy to propagate by division or simply by digging a few thick roots while dormant or just as new foliage appears in autumn. Well watered plants can keep their foliage all year, so that they only need to be groomed of older foliage and spent flower stalks. Partial shade is not a problem; although snails can be.
Big arching leaves form bold mounds of glossy foliage about three feet wide. The distinctively lobed and toothed foliage has an appealing texture and deep green color. Elegant mostly white flower spikes stand nearly five feet tall late in spring into summer. Acanthus balcanicus (illustrated) is more compact, with more intricately textured foliage.
Several species of Phlox are native California wildflowers. Yet, the more popular garden phlox, Phlox paniculata, is native only east of Kansas. It can self sow where it gets water, and is naturalized in the Pacific Northwest. It prefers rather rich soil and sunny exposure but is not very discriminating. A bit of partial shade might promote taller stems for cutting.
Mature garden phlox can be as tall and wide as three feet. Some modern cultivars stay a bit more compact. Dense panicles of small flowers may be as wide as six inches. Bloom is most commonly white, but may be pink, red, lavender or pastel orange. It is a splendid cut flower, with an alluringly rich fragrance. Bloom might continue for a month of summer.
Garden phlox is deciduous, so all canes die to the ground for winter. Mature colonies are then easy to propagate by division. Similarly, feral specimens that appear where they are unwanted are easy to relocate. Garden phlox can perform nicely in proportionately large pots and planters. It is uncommonly available from nurseries, but grows easily from seed.
Curve leaf yucca is one of a few species of the genus that is difficult to identify. It may be a distinct species, Yucca recurvifolia. It may be a naturally occurring variety of mound lily, Yucca gloriosa var. tristis or recurvifolia. Yet, it may be a natural hybrid of Yucca aloifolia and Yucca flaccida. To complicate all of this, its physical characteristics are inconsistent.
The evergreen leaves of curve leaf yucca are typically pliable, and curve downward. Yet, they can be quite rigid and upright. Foliar color is typically grayish green but can be olive drab. Stout but upright trunks can potentially develop, but may never do so. Only their tall floral stalks that bloom for summer are consistent. Individual flowers are small and white.
Curve leaf yucca enjoys warm and sunny exposures. Occasional watering through warm weather may improve vigor, but is unnecessary. Old colonies form large mounds that can slowly grow as high and wide as ten feet. With the exception of gophers, which eat roots, not much bothers curve leaf yucca. In fact, it can be very difficult to eradicate if unwanted. Pups may continue to develop from rhizomes for many years.
The pinkish magenta of rock purslane bloom is almost obnoxiously bright.
In Santa Cruz and coastal areas down to Los Angeles and San Diego, rock purslane, Calandrinia spectabilis (grandiflora) has been popular for only a few years. It is still somewhat uncommon here in the Santa Clara Valley. Because of the ambiguity of its Latin species name, it is most commonly known simply by its genus name of Calandrinia.
Moderate watering is best. On the coast, rock purslane only needs water occasionally through the driest summer weather. It should recover readily from winter frost damage. Partial shade is not a problem, but may limit profusion of bloom. Harsh exposure or reflected glare can actually roast the tender succulent foliage.
From about now through autumn, limber, two foot tall stems suspend strikingly bright magenta flowers above the low, grayish evergreen foliage. The fragile leaves are neatly arranged in terminal rosettes. Foliage, stems, flower stalks and all parts are sensitive to traffic, and can even get broken by a cat sneaking through the garden. Broken bits and pieces of stem root very easily to make new plants, though.
The most familiar lawn grasses can not do what the many other grasses and grass like plants do in a garden. Lawns are mown into submission so that they can function like carpet in outdoor rooms. They certainly have their appeal and practicality, although they require very regular maintenance and generous watering.
Other ornamental grasses are grown like more common perennials, to provide appealing foliage, flowers, forms, textures and ‘motion’ as they move in even slight breezes. Most require significantly less water and maintenance than lawns do. Sedges, rushes and papyrus, although not grasses, function like grasses around ponds and in areas that are too damp for grasses to be happy.
Giant reed, pampas grass and bamboo are all notorious as invasive weeds. Giant reed and pampas grass appear and grow voraciously in some of the worst places that their seeds can get into. (Giant reed should not be planted anywhere near waterways or riparian environments.) Bamboo is not nearly as prolific, but spreads aggressively by stolons (subterranean stems) that grow very fast and potentially reach several feet.
However, where they can be contained, these three are the boldest of their kind. Giant reed grows like large types of bamboo, but fluffier, with broader undivided leaves. Pampas grass develops into big mounds of graceful foliage with billowy white or pinkish flower plumes. (Pampas grass leaves can cause nasty paper cuts, though.) The many different types of bamboo provide a variety of graceful foliage; and many provide striking form with their rigid canes. Some bamboo are low and compact. Most are tall and elegant.
Dwarf blue fescue is among the smaller ornamental grasses, forming round tufts of soft but seemingly bristly blue foliage that resembles dense bundles of pine needles. Fountain grass is considerably larger, with green or purplish foliage, and flower plumes that look like kitten tails. Hair grass is so softly textured that it barely supports its own weight, and often lays gently on the ground or leans onto other plants.
Except for giant reed, pampas grass and the various bamboos, most ornamental grasses do not need much attention. Some look better if they get cut back before they start to grow at the end of winter. Others should get their fading flowers removed. A few are deciduous, so die back over the winter. Grasses are otherwise easier to care for than any lawn and many other perennials.
Only riparian and aquatic vegetation tolerates sustained soil saturation. Chilean rhubarb, Gunnera tinctoria, almost qualifies as such. It enjoys such generous irrigation that it may perform well on a bank of a pond or stream. However, it should be sufficiently high on its bank to avoid constant saturation. Otherwise, it can rot, likely during its winter dormancy.
Chilean rhubarb is a spectacular foliar plants. Its humongous lobed leaves may grow six feet wide and eight feet tall. Although they succumb to mild frost, they regenerate quickly from rhizomes for spring. Leaves and petioles have a rather raspy texture, with small soft spines. Odd conical floral spikes that bloom about now might grow nearly three feet high.
Although not related to real rhubarb, Chilean rhubarb is as edible as its name implies. Its big petioles only need peeling to remove the raspy exteriors. Locally, Chilean rhubarb is more of a striking ornamental perennial. It is as appropriate to woodsy gardens as it is to sleek modern gardens. The absence of its bold foliage for winter is the main disincentive for its usage.
What makes this particular white bearded iris so special? Well, all three of the bearded iris that bloom white in my gardens are special. Each arrived with history, from other important gardens. I am impressed with this one now because it is so white. I did not know what color it was when I acquired it from its garden in Monterey so many years ago. I just wanted a souvenir from that particular garden after the owner passed away, so grabbed a bit of it during the estate liquidation. It bloomed for its first season, but was a dingy grayish white. I thought it might get whiter for its second season, but continued to bloom annually with the same unimpressive color. I could not eliminate it from my collection because of its historical significance. Because it is so uninteresting, I had not shared it or, until recently, tried growing it anywhere else. Then, because bearded iris grow and proliferate as they do, I brought a small bit of it to the Iris Bed at work, where I got this picture of it. I can not explain why it is so much whiter than it had been, but I am impressed.
Tony Tomeo 