April 30, 2007
By Julie MonsonFor the part of my garden that is accessible to deer and gophers, I am constantly on the lookout for hardy, evergreen shrubs that can serve as a defining backdrop to bulbs and perennials, and that are ignored by deer and gophers. I also prefer shrubs that, along with small trees, help create the “bones” or structure for sections of the garden. Choisya ternate, sometimes called Mexican Orange, is one of the dark green, evergreen shrubs that thrives in our climate, and nicely meets all of these requirements. It is amenable to shaping, and can easily serve as an informal hedge or as a specimen plant where a splash of white is just what you need.
I first noticed Choisya, before I knew what it was, along the neglected fence of a neighbor’s garden, blooming cheerfully and totally ignored by deer. It was obviously hardy, surprisingly pretty, with 4- 5-inch clusters of white flowers glowing against dark, glossy green leaves. Surely, if it could survive such neglect at a neighbor’s, it was worth considering for my garden.My next encounter was in the elegant garden of Sarah Hammond in Bolinas. Sarah, now moved to Arizona, was a consummate, well-organized gardener who gradually simplified her plant palette to fewer plant varieties, concentrating on those that contributed shape to her garden, thrived easily and produced bountifully. Her specially selected roses were legendary. One of her favorite shrubs was Choisya, for its vigorous bloom in late winter/early spring. In a winter 2004 newsletter, she described its “unexpected whiteness” and her “gratitude to gophers who mercifully bypass this plant.” She goes on to tell us, “I like to think their avoidance is horticultural poetic justice when in fact I know the reason is that Choisya is of the Rue order and therefore unpleasant to gophers, deer or any creature who would dare to munch.” Rue (Ruta graveolens), and Breath of Heaven (Coleonema) in the same family, also deter munching pests.
The leaves of Choisya form at the end of branches in fans of 3, up to 3-inches long. On the same plane are the clusters of white flowers, similar to orange blossoms, that bloom all over the plant, creating an informal bouquet of white flowers contrasting with the lush green leaves. The leaves have a spicy fragrance when pinched while the flowers are only slightly fragrant. Choisya is a handsome addition to indoor bouquets, a useful way to use outer branches thinned by occasional pruning. It prefers a slightly acid soil and good drainage, modest water, and is said to be susceptible to damage from sucking insects and mites. I have not yet had that difficulty, but I keep a watch for it.
”Sunset’s Western Garden Book” tells us that Choisya ternate is fast growing to 6-8 feet tall and wide. In a partially shady corner of my West Marin garden it grows more slowly and responds well to modest pruning to control its shape. In a warmer garden, it would surely grow more quickly. Mine have been flowering since late January, and at the moment, are spectacular near a white blooming dogwood. White flower clusters, against the variegated dark, lustrous, and pale greens of the rest of the garden, are always surprisingly stunning. I have four Choisya, now 4-5 feet tall and wide, forming an informal, blooming hedge 20 feet long. It is complemented by a foreground of iris, variegated society garlic (Tulbaghia violacea) and Australian fuchsia (Correa), filling a large partially shady area that five years ago was bare.
Other standard bearers for relatively large, flowering, evergreen shrubs that serve well to create garden structure include camellia, rhododendron, viburnum and pittosporum. Native plants that serve the same purpose include coffee berry, huckleberry and ceanothus. I use some of these, but for the moment, my favorite is Choisya.