JARS v60n3 - Landscaping with Rhododendrons

Landscaping with Rhododendrons
Peter Kendall
Portland, Oregon

The topic - landscaping with rhododendrons - embraces far-flung and disparate possibilities. From the tropical or near tropical, to areas hot and humid yet frigidly cold at intervals, to other comparable marginal locales, to areas of temperate bend, one must adapt to one's situation to achieve the most satisfactory outcome.

In what I consider fortuitous, my residence in the Pacific Northwest offers me a range of opportunity with a universe of acceptable selections. Moreover, my microenvironment in a particular part of the temperate upper Willamette Valley accentuates my good fortune.

Designing with rhododendrons begs a larger question - what design principles shall we rely upon to stage the most effective or appealing coming together of our choices? Within my thirty-five years in the horticultural world, perhaps my greatest influence in an approach to design lies in two places. The first resides in the limited writings of John and Carol Grant, Trees and Shrubs for Pacific Northwest Gardens, Garden Design Illustrated, and the second in the treasure tome of offerings in the Japanese tradition. Both influences have common denominators - they are acutely sensitive to nature in a particular setting and they employ elements that subtly bear upon an artful outcome.

As landscape architects, John and Carol Grant were among the most respected of mid 20th century practitioners of garden design in this part of the world. The culmination of their impact issued from some very basic axioms when it came to laying out a plan. The initial approach dictated a choice between a formal or informal setting. With a formal setting, a regimented scheme with symmetrical balance and straight lines prevails; with an informal setting, natural or free flowing contours with no straight lines and an asymmetrical balance holds forth.

Scale is an integral consideration when it comes to determining what choices to make. Large trees and shrubs tend to tie hard architectural features to the ground and make those structures appear smaller; the smaller the trees and shrubs, the more dominant the hard architecture. Trees, in particular, provide a canopy or "sphere of influence" under which smaller shrubs (and ground covers) may often flourish. Their size and shape may be judiciously altered by thoughtful pruning remembering that space within and among plant elements is all-important.

According to the Grants, plant material in garden design falls into discrete categories according to the light reflecting properties of each category's foliage. Conifers (trees and shrubs) with their needle-like foliage absorb the most light and thus tend to be the most aesthetically heavy; this is extended by their generally year-round presence. They should be used reservedly to avoid an overly ponderous or funereal effect. Broadleaved evergreens, among which most rhododendrons fall, reflect a good deal of light year-round and may be used with much more abandon. Given the gamut in stature, texture of foliage and flower color, this is most advantageous for rhododendron aficionados. Moreover, the use of rhododendrons from large specimens, to carefully selected plants for foundations, to rock gardens, to containers is overridingly enticing. Finally, deciduous material reflects the most light in its seasonal dalliance, with its tracery often an added bonus during its absence of foliage in winter.

Only after consideration of the above plant materials, should consideration be given to herbaceous material (including vines) to augment the character of the garden and to bring together disparate elements.

As alluded to earlier, exposure to some of the cardinal tenets of Japanese garden design has greatly influenced my approach to conceptualizing a garden. Among those principles is the "hide and reveal" technique of the traditional stroll garden whereby the surprise of an opening vista gives the feeling of spaciousness in a relatively restricted area. This goes hand in glove with nuanced curves and asymmetry in the placement of groups of plants along traveled corridors. The use of "scenery borrowed" from beyond the premises of the garden may additionally enhance the quality and perceived extent of a particular location.

The use of exotic material from stone, to structural wood, to plant material should be compatible with the natural or indigenous wherever or whenever employed. When it comes to plant material, a focus should be on a monochromatic green tableau with the color of foliage and flower principally of seasonal character.

As you may gather from the above pronouncements, my special affection is for the small woodland garden. Again, my situation allows me the fortune to select from a broad palette when it comes to choosing particular plants among which rhododendrons may be prominently featured. I offer photographs with a list of options which hopefully enhances the focus I intend to convey.

Peter Kendall, a landscape designer, is a member of the Portland Chapter and frequent contributor to the Journal.