A Whiff of the South
Sweet Olive and Its Hardy Relatives Can Thrive Here.
By Rachel Foster 12/9/04

A long fall weekend in New Orleans! Aside from the odd shower, the weather was friendly, and it was pleasant to be warm again. Our hosts at Tulane University put us up in a hotel on St. Charles Avenue, where the streetcar runs to this day and takes you most places you'd want to go. Half a minute's walk away were the mansions of the affluent Garden District, which deserves its name, more or less. The impoverished Lower Garden District nearby was more interesting by almost every measure, not least because its gardens, though relatively few, were more relaxed, less predictable and contained a greater variety of plants.
It was in the Garden District proper, though, with its carefully manicured and formal evergreen front yards, that we detected a sweet, fruity, pervasive scent. I soon tracked it down to the sweet olive (Osmanthus fragrans), an upright, evergreen shrub that ages to a small tree and produces little tubular white flowers from September through spring. In the Garden District it occupied a significant fraction of the airspace between the ubiquitous camellia and podocarpus hedges and the majestic live oaks soaring and dipping overhead.
The sweet olive fragrance might be overwhelming on a really warm afternoon. On a mild day it's perfect, and slightly elusive: one of those odors that you catch in waves, sometimes quite a distance from the source. Out of curiosity, I looked the species up when I got home. Sunset Western Garden Book lists sweet olive as hardy in the Willamette Valley, but most writers consider it the least hardy of the genus, which would make it too tender for the valley. It might grow in mild areas along the coast.
Sweet olive has several hardier relatives. None, as far as I know, will bloom all winter, but several bloom either late or very early in the year, joining a host of other shrubs -- witch hazel, daphne and viburnum, to name a few -- that flower sweetly during the colder months. One of the most useful species for West Coast gardens is fall-blooming Osmanthus heterophyllus, called holly-leafed osmanthus because the leaves on young plants closely resemble those of English holly, prickles and all, but I have never found them quite as stickery. It grows to 10 feet and beyond, and the leaves on mature stems are less spiny.
My favorite variety of this plant is Osmanthus heterophyllus 'Purpureus,' which has slim leaves that are actually purple only on new growth but always remain a bit darker than those of the species. A five-foot specimen in my garden bloomed for the first time this fall and the white flowers positively sparkled against the leaves. There are also several variegated forms, of which I have grown only one, O. heterophyllus 'Variegatus.' This is an excellent plant for filling pots in winter. Even small plants have impact because of the bright, irregular cream margins on the glossy leaves. The foliage of another nice form, 'Goshiki,' is pinkish when new, then green, speckled cream and gold.
Variegated forms of holly-leafed osmanthus are slower growing than the solid green varieties. This makes them easy to maintain in containers and also makes them useful as manageable, medium-low hedge plants. Another species with small green leaves makes a good broad hedge or screen, and is relatively easy to maintain at 5-6 feet: this spring-flowering hybrid, Osmanthus x burkwoodii, is vigorous and tends to grow wider than it is tall. Like most osmanthus species it grows in sun or light shade, but is not hardy enough for very exposed locations.
Lastly, there's Osmanthus delavayi, probably the least hardy of the osmanthus species worth growing in the Eugene area but one of the most decorative. The leaves are dark green, a bit holly-like and tiny, scarcely one half inch long, providing an unusually fine texture for a non-coniferous evergreen. The usual white flowers appear very early in spring, with the usual osmanthus fragrance. But they appear in every leaf axil along the many slender stems, giving the shrub a distinctive, star-spangled look that is particularly striking from a distance.
I think everyone should try this plant, just bearing in mind that it may die in a really cold winter, should we ever see such a thing again. Mine was planted near a path, where I am forced to prune it every year. After at least five years of this treatment it is still a very small shrub. On the basis of this experience alone, I'd say it is a plant that is easy to keep small. I have never grown one as a potplant, but the large, nice-looking container grown specimens I often find in nurseries suggest it would be happy to continue living in a pot.