A Sentimental Favorite
Mock Orange Makes a Great Background Shrub.
By Rachel Foster 6/8/06

Ah, the sweet scent of mock orange! Out of bloom, this big thicket of a deciduous shrub has little to recommend it, but months of drabness are instantly forgiven when you experience that avalanche of flower and fragrance. Mock-orange (Philadelphus) blooms as spring gives way to summer, its perfume mingling with that of roses, to which the pure white flowers of mock orange are a perfect complement. No wonder it's a favorite background shrub for old fashioned rose borders.
Classic mock orange varieties such as Philadelphus coronarius and "Virginal" can grow to 10 feet or more in height and girth. If that seems a bit much for your yard, it is good to know that smaller varieties exist. In the gardens at Gossler Farms Nursery in Springfield (open by appointment: 746-3922), I fell in love with Philadelphus microphyllus in full bloom. This Southwest U.S. native forms a four-foot mound of gracefully arching branches. It isn't currently listed in the Gosslers' catalog, unfortunately, but they do sell two decidedly dwarf varieties, both with showy double flowers: "Snowbelle" (three to four feet tall) and an even more petite, mound-shaped grower named "Manteau D'Hermine."
The Pacific Northwest has a wonderful native mock orange. The flowers of Philadelphus lewisii are small but numerous, and they are deliciously fragrant. In natural settings the plant can grow anywhere between four and 12 feet, depending on location. Tall specimens arch elegantly. It has a moderate growth rate, and in gardens without much summer water, annual removal of the older limbs might keep it to five or six feet. In good garden soil with abundant nourishment and regular (though moderate) water, it can give those big hybrids a run for the money. P. lewisii will not tolerate wet soils, and like all mock oranges it flowers best in sun.
One of my favorite mock oranges is "Belle Etoile," which grows from five to eight feet tall, depending on whom you ask. I have personally never seen one reach eight feet. It is one of a number of old French hybrids that have a maroon blotch at the base of each large petal. Roger Gossler says he used to have a devil of a time keeping up with demand for this plant, but now it isn't "moving." He also says the maroon blotch is not as pronounced as he would like, but he admits it's a nice plant. When I asked him to name a better philadelphus, he suggested "Fallbrook." His potted specimens showed impressive snow-white flowers that open flat, spreading over two inches across.
Having said that mock orange makes a dull bush, I should mention some variations in leaf color. "Innocence" is a tall grower with very large, cupped flowers and a good scent that happens to produce new leaves generously splashed with cream. The variegation is less conspicuous in mature foliage. Philadelphus coronarius "Aureus" has pure yellow leaves -- golden in strong light, chartreuse in shade -- and small, very fragrant flowers. Gossler suggests a little afternoon shade. "We had it in full sun for a while," he says, "and it did fine 'til late July, then the color started to burn out."
Lastly there's P. coronarius "Variegatus," the leaves of which have broad white margins and the variegation doesn't fade as leaves mature. It makes a striking accent in a shrub border. "You wouldn't notice the flowers much, except for the scent," Gossler says. Like other strongly variegated plants it's a slower, smaller grower than the all-green parent species.