A dialogue among rock, sculpture, and the craggy forms and wild demeanors of plants that thrive in a dry climate—such is the nature of our nine-year-old North Berkeley garden. We started out with the idea of combining stones and plantings in an informal way to emphasize the sculptural qualities of drought-tolerant species. We wanted to compose these plants with some of the three-dimensional artwork we had been creating using mainly natural materials (with the occasional quirky additions of colored tile or grout surfaces).
Rather than draw a garden plan on paper, we began impulsively by creating several stone features to acknowledge the boundaries of the space—a typical, modest-sized, flat city lot with mostly sunny exposures. A massive dry-stacked stone wall along the public sidewalk that edges the front yard created a visual frame for the site. In a protected corner of the back yard, a heavy wooden slab carved from a split oak log was nestled within a group of boulders in a simple arrangement at the end of a path, thereby creating a solid, quiet destination at the far corner of the garden. In both of these works, we emphasized the intrinsic form and texture of the natural materials so that the evidence of human artistry was secondary to the beauty of the material.
A long process of trial, error, and soil preparation finally led to the garden as it appears today—a celebration of the forms of a diverse collection of drought-tolerant species in unusual combinations and settings. Among the dominant plants are sharp and dramatic specimens of agave, cordyline, and dasylirion, combined with softer forms of muhlenbergia and salvia, and woody manzanitas, tea trees, and palo verde trees. We worked with a palette of foliage color and texture: some plants rigid and spiky, others grassy and kinetic, or leafy and complex. Flowers, a temporal presence, were often chosen to harmonize rather than contrast with the foliage.
As our expanding collection of native and exotic plants began to find homes among the stone and wood features that we had initially created, we added more elaborate and eccentric objects crafted of recycled lumber, troweled cement, and tile mosaic. These newer pieces acknowledged a stronger human presence in the garden than the earlier works had done. Our burgeoning rock collection was shaped, in time, into pathways as well as additional naturalistic compositions.
Front and Back Gardens
Today, passersby on the street see the front garden with a 1920s Mediterranean-style house as a backdrop. Against the white stucco of the house, strongly vertical plants stand out: Cordyline australis ‘Albertii,’ Phormium ‘Guardsman,’ both with colorful, swordlike leaves, and a Leptospermum lanigerum, a tea tree with extra-fine silvery foliage and an oddly weeping habit. The skeletal form of a columnar cactus (Cereus peruvianus) towers over other dryland natives including desert spoon (Dasylirion wheeleri) and a small hybrid agave (Agave scabra x ferdinandi-regis). The terrain is rocky, and the dry wall that delineates the garden’s front edge, three feet high at the corners, steps down gradually toward a central path, giving way to the fullness of adjacent plantings of echeveria, California fuchsia (Zauschneria), California poppy (Eschscholzia californica), and various stonecrops (Sedum). Wood and barbed wire sculptures echo and play off the grassy and spear-like forms around them, adding geometric and handmade qualities to the broader tapestry of foliage.
The back garden, more contained and bounded by neighboring houses, is divided into a complex layout of beds and pathways; plantings often surround a visitor moving through the space. Unlike the front garden, with its stagelike orientation to the street, the back is a composition of vistas that shift continuously as one moves along the paths. At one end is a somewhat moist and shady corner, planted with Brugmansia ‘Charles Grimaldi’ with pendant trumpets of soft butterscotch, a rush-like restio (Elegia capensis), Bambusa tuldoides, and the red orange floral spikes of Salvia confertiflora. To the north is a more open, drier site filled with hybrid kangaroo paws (Anigozanthos ‘Pink Joey’), the graceful wands of Dierama pendulum ‘Robustum’, and Phormium ‘Dusky Chief’. Further along, in an area of sun and reflected heat, are more agaves (A. desmetiana ‘Variegata’ and A. americana ‘Mediopicta’) under the delicate canopy of a palo verde (Parkinsonia aculeata), along with Phormium ‘Yellow Wave’, and Euphorbia rigida.
Many of our more eccentric sculptures were placed in the back garden. An oversized goblet surfaced in purple and red mosaic holds a corkscrew rush (Juncus effusus ‘Spiralis’), which sometimes catches an overflow of Clematis ‘Jackmanii’ when it runs out of room on the nearby trellis. A quartzite- and tile-clad tower, just four feet tall, plays with scale in this space, suggesting height but dwarfed by a neighboring bottlebrush (Callistemon citrinus ‘Jeffersii’), crimson-flowered Cestrum ‘Newellii’, and another dierama.
Although the garden’s design came about in a somewhat haphazard fashion, we attempted to keep the plant associations believable, alluding to natural combinations while enjoying considerable creative license. Characteristics of light, soil, and reflected heat in the various areas of the garden allowed for some distinctly different communities to evolve. By choosing plants that would thrive in a particular microclimate, a pattern gradually emerged: an exotic collection of plants coalesced into a community, and relationships between plants became more specific. For example, a large specimen of Abutilon ‘Souvenir de Bonn’ supports a twining Bomarea caldasii, whose heavy clusters of orange and yellow, almost pendulous flowers appear amidst the abutilon’s large, variegated, maple-like leaves. A mound of purple-leaved Heuchera ‘Amethyst Myst’, situated at the base of a large gray stone, met with the cream and mauve blossoms of ‘Purple Gleam’ California poppy.
While these individual relationships flourished, the larger layout of the garden was unified in two ways: by attention to the interaction of color and form of neighboring foliage; and by working with the whole as a three-dimensional landscape painting in which every plant, rock, and object contributes to the overall balance of size, shape, and texture—from large and imposing to small and intimate, and from hard and sharp to soft and delicate.
The Garden Matures
As the garden evolved to a mature state, we learned many practical lessons about soil and exposure and gained a stronger grasp of aesthetic considerations: the impact of plant and stone combinations, distinctive foliage and color palettes, and the beauty of serendipity as plants volunteered to fill vacant pockets in the garden.
When planting first got under way, it was apparent that the soil needed considerable work. A process of lightening and mounding the native clay moved along one hole at a time, but, despite good intentions and much lava sand, the proteaceous shrubs (Grevillea and Leucadendron) that were part of the initial planting proved to be short lived. About the same time, it became apparent, through the decline of the city’s street trees (camphors), that oak root fungus (Armillaria) was a factor in the front garden. Once the camphors were removed, the front yard was much more exposed; it was almost a “blank canvas” again, except for a few early survivors: bottlebrush, another restio (Chrondropetalum), and the columnar Cereus.
As subsequent rounds of planting took shape in the now much sunnier front yard, we substituted tea trees and bottlebrushes for the disappearing proteaceous shrubs and reduced the overall number of woody plants in response to the oak root fungus. Agaves, euphorbias, and red hot pokers (Kniphofia) began to spring up from among the random drifts of stone that remained from the wall-building process, suggesting a harsh and dramatic terrain. As we observed the impact of these combinations, we made the play between plants and stones more intentional. The stone surface began to function as a backdrop, providing local color and texture against which the plantings were seen. In one warm area, clustered around an oblong, light gray stone, were the blue gray foliage of Euphorbia rigida and Agave parryi, plus Phlomis aurea, and Phormium ‘Apricot Queen’; the euphorbia’s spiraling leaves played delightfully against the solidity of the stone and the agave. The phormium and phlomis, both with yellowish foliage, joined with the euphorbia each winter to create a glowing mass of yellow and chartreuse.
Some of the more successful plants in the garden’s early stages were agave relatives (Cordyline australis, Hesperaloe parviflora, and various Phormium hybrids), but soon we needed some relief from all the spikiness. Salvia confertiflora, kangaroo paws, and a feather grass (Stipa ichu) brought a softer, more flowery quality while the surprising and quirky character of honey bush (Melianthus major), Ovens wattle (Acacia pravissima), and a South African cabbage tree (Cussonia paniculata) expanded the possibilities for distinctive foliage to contrast with its surroundings. Eventually, some surprising juxtapositions of flower and foliage revealed themselves. We were struck, for instance, by a giant feather grass (Stipa gigantea), planted almost beneath a manzanita (Arctostaphylos pajaroensis), sending its light-catching golden inflorescences upward through the manzanita’s zig-zagging branches and bronzy red new growth.
A similar example showed itself one spring after I planted a dormant purple smoke tree (Cotinus coggyria ‘Purpureum’) near an established clump of Euphorbia characias ‘Lambrook Gold’. Anticipating an overlap between the euphorbia’s chartreuse floral bracts and the smoke tree’s new burgundy foliage, I awaited the combination with curiosity and some trepidation. I discovered, however, that the expanding leaves of the smoke tree were perfectly balanced by the gradually mellowing chartreuse of the euphorbia. The smoke tree’s new foliage and the fading euphorbia remained a captivating sight, even after the latter’s seeds had begun to disperse.
From experiences such as these, I also developed a penchant for watching flowers fade and seeds develop, which, in turn, resulted in a proliferation of volunteer seedlings. Most satisfying were those of false sea holly (Eryngium planum), which thrived in a narrow strip of clay between the front wall and the sidewalk and produced a striking display of silvery blue umbels up to three feet high. Euphorbia myrsinites scrambled atop the rocky mulch, staying low and rarely more than two feet wide, its glaucous foliage lit up by lime gold floral bracts in spring. One of the New Zealand sedges (Carex testacea) almost always volunteered in a spot preferable to where I initially planted it, and its mass of fine orange bronze blades provided a beautiful foil for almost any plant that grew nearby. Moreover, it thrived on little water and virtual neglect.
As the diversity of plants increased, I became intrigued with combining similar colors, reducing the frequency and degree of contrast. In the warmest beds in front, the blue gray foliage of desert spoon, a prickly pear (Opuntia robusta), California fuchsia (Zauschneria ‘Roger’s UC Hybrid’), and Euphorbia myrsinities were seen against creamy Phormium ‘Cream Delight’ and pink, green, and cream Cordyline australis ‘Albertii’. Flowers contributed warmer hues here: orange Kniphofia ‘Goldmine’, maroon red drumsticks (Allium sphaerocephalum), brick orange Euphorbia griffithii ‘Fireglow’, and apricot Indian mallow (Abutilon palmeri).
As the plants changed and the garden matured, I felt a sense of wonder as I watched each plant move through its cycles of growth and rest. This wonder, a basic motivation in my work with plants, began in childhood, when I first observed the flowering of a century plant (Agave americana). As a child I had no understanding of what I was seeing as the stalk shot up to treelike proportions, then flowered, and formed seeds, yet I was in awe at this clear manifestation of the life force and life cycle of a plant. At the same time, I was captivated by the agave’s stark, sharply delineated form, which set the tone for the types of plants that, to this day, seize my imagination with their dramatic structural beauty.