When the phrase 'flowering trees and shrubs' comes up, it is generally accompanied by mental images of great spring-time drifts of pink Cherry blossoms, white Dogwood bracts, the occasional Magnolia, or a flock of Forsythia flowers. As with many things, we tend to focus on the massive, one-time show, neglecting the subtle, long lasting, or more delicate alternatives for that sure-fire, all out blast. There are, however, thousands of wonderful trees and shrubs whose flowers (and other characteristics) bring delightfully understated elegance to the landscape for long periods of time (if we will just give them a chance...). Mexican Orange, Choisya ternata, is one such evergreen shrub.
Mexican Orange is a member of the same botanical family as roses, the Rosaceae, and bears flowers with a similar, though less intense, fragrance than its more familiar sibling, the rose. Mexican Orange is an evergreen shrub with a pleasingly round and mounded habit. It will eventually reach heights of 8 - 10 feet with an almost equal spread. The deep green, glossy leaves are a rather perfectly archetypal leaf shape - about 3-4 inches of smooth oval tapering to a softly pointed tip - and are arranged in groups of three, like small, three-fingered hands. The leaves of this shrub are so glossy and perfect that I have been asked if they were plastic!
The general appearance of Mexican Orange is that of a contented dark green cat sitting and purring with a rounded head atop curved shoulders, hips and curled tail. The foliage is beautiful all year, retaining its shining elegance through the winter, but Mexican Orange also bears delicate, bright white flowers with a light, rosy fragrance. Although their fragrance is rosy, the flowers look very much like the flowers of true Orange, hence the common name of Mexican Orange. Flowers are borne in the greatest profusion in late spring but there is often a secondary bloom in the early fall and sporadic flowering can occur most any time of the year when the temperatures are not extremely hot or cold.
The early fall bloom of Mexican Orange is a delightful reminder of spring and summer in the garden and is a special surprise at a time of the year when the mood of the garden turns toward the bronze and red colors of falling leaves. It makes a lovely specimen plant or a massed grouping in the same way that most broad-leaf evergreens do.
Mexican Orange prefers well-drained, moist, slightly acidic soils in full sun or partial shade but it has performed well in the Piedmont clays at The NCSU Arboretum (now the JC Raulston Arboretum). It is not hardy in the mountains of the southeast but will survive most Piedmont and Coastal plain winters and thrive in those areas. It can be propagated by summer softwood cuttings rooted under mist.
One cultivar of Mexican Orange is 'Sundance' with sunflower-gold foliage. The new foliage is the brightest gold and gives the most color during the late winter when it is a superb way to brighten winter gardens.
At The NCSU Arboretum (now the JC Raulston Arboretum), Choisya ternata, surprises visitors as they enter the Shade House with delicate white flowers sprinkled among shining foliage, even in the fall, and is a welcome reminder of the effectiveness of a beautifully subtle floral display - an intriguing alternative to mass production in the landscape, in any form. br>