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.
Even for some understory species, shade can inhibit bloom. For Hosta, that would not be much of a problem. Its late summer bloom is merely an added bonus to its lushly colorful foliage. Actually, the foliage is more appealing without its tall floral spikes. Such bloom is prettier in a vase anyway. The hanging white or lavender flowers are an inch or two long.
Where summer weather is cooler, some Hosta can grow three feet tall and twice as wide. Locally, only a few of the largest cultivars can grow as wide as three feet during summer. Then, they defoliate by winter. Most have broadly rounded leaves, but a few have narrow or wavy leaves. Many have paler green, yellow or white variegation, or glaucous foliage.
Hosta is uncommon here, probably because it may be somewhat demanding. It requires very regular watering to avoid desiccation. It craves organically rich soil or potting media. Fertilizer can enhance lushness, but can burn foliage if just slightly excessive. Slugs and snails can ruin foliage. However, Hosta are understory plants that tolerate a bit of shade.
Oem is beginning its third spring here. Fortunately, it has not yet grown too big to stay. That could change soon now that the weather is warming. I still do not know what to do with it as it grows. It is the largest species of banana in the World, Musa ingens. The foliage of the original pseudostem was frosted enough last winter to get trimmed away, leaving only an unsightly bare trunk. It is only beginning to replace its foliage for this season. Just as readily though, it produced two pups, which will likely grow faster than the original pseudostem did during the last two seasons. They are growing from a larger rootbase. Meanwhile, there are several other cultivars of banana growing here also. There were about fourteen last year. There are about two dozen this year! Only a few will remain compact enough to inhabit the landscapes at work, but even fewer will be appropriate there. Banana trees are not exactly comparable with the style of a redwood forest. Most, including the oem, will likely inhabit a riparian area of my home garden, which is also in a redwood forest. Goodness! I really should have planned this better.
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.
Tony Tomeo 