Osmanthus is a genus in the family Oleaceae. The name comes from the Greek words osme meaning fragrant and anthos meaning flower. Consisting of about 30 species of Angiosperms (flowering plants), most Osmanthus are native to subtropical eastern Asia. A few are native to Caucasus, New Caledonia and Sumatra. One or two species are found in North America.
All Osmanthus species are evergreen shrubs or petite trees. Leaves are simple, serrated, spiny and covered with glands similar to the appearance of holly. White or yellow flowers are hermaphrodite, though usually become unisexual, and have two to four stamens. The fragrance is akin to jasmine, orange blossoms and ripe peaches or apricots. These showy blooms bear fruits that are bony or hard in texture.
|Botanical Name||Osmanthus genus|
|Common Names||Tea olive, Sweet olive, Sweet osmanthus, Fragrant olive, Fortune's tea olive, False holly|
|Plant Type||Flowering evergreen shrubs and trees|
|Mature Size||20 to 30 ft. tall|
|Sun Exposure||Full sun|
|Bloom Time||Spring, fall, intermittent|
|Flower Color||White or yellow|
|Hardiness Zones||8-11, USA|
|Native Area||Eastern Asia|
Resistant to many pests, able to withstand heavy pruning, and adaptable to a variety of soils, Osmanthus are a beloved choice of landscapers in Mexico and the southern United States. These plants like plenty of space as, depending on the variety, Osmanthus can grow between 15 and 30 feet tall.
Plant in full sun. Offer part afternoon shade in hot summer climates.
Osmanthus will grow easily in any good garden soil, tolerating heavy clay and even chalk. Average, moist, well-drained soil is best.
Watering needs are medium and the plant is drought-tolerant once established.
Temperature and Humidity
These plants are typically winter hardy to about 10 degrees Fahrenheit, thriving year-round in USDA Zones 8 through 11.
Is Osmanthus Toxic?
There are no known toxic properties in Osmanthus plants.
Varieties of Osmanthus
The different species vary considerably in size, leaf shape, and color. Some popular examples are outlined below.
- Tea Olive trees (Osmanthus fragrans) are what around 15 of the 30 or so varieties of Osmanthus are known as. They are also known by the names sweet olive, sweet osmanthus, and fragrant olive. Their white flowers can be steeped in tea as the Chinese do. They are native to Eastern North America, Hawaii, Mexico, southeast Asia and New Caledonia.
- Devilwood (Osmanthus americanus) is an American native variety. It is the only species of tea olive that tolerates salt spray, making it ideal for coastal locations. Because it is sometimes considered invasive, gardeners in St. Louis, Missouri, for example, grow it in containers.
- Holly Tea Olive (Osmanthus heterophyllus) is known as "false holly" due to its pointed leaves which are especially resemblant of holly bushes. This plant blooms in late fall and can reach a height of 15 feet. A year after the fruit is produced, it ripens.
- Fortune's Osmanthus (Osmanthus x fortunei) is a hybrid of O. fragrans and O. heterophyllus. Also called Fortune's Tea Olive, this one blooms in late fall, too, and grows 20 to 25 feet tall.
While most varieties bear white flowers, some, like the Golden Osmanthus (a variety of Osmanthus fragrans), pictured above, have yellow flowers. These blooms are heavenly fragrance, and the Japanese and Chinese make use of the plant's healing detoxifying and anti-inflammatory properties.
Osmanthus can be trained as a small tree, shrub or espalier. Clip its tips to encourage growth and maintain the desired size.
To propagate by cuttings, root in the warmth of summer. Grafting and seed propagation is possible, though generally not as successful. Osmanthus grows best on their own roots.
Growing Osmanthus in Containers
South of USDA Zone 8a, sweet olive is grown as a flowering tree, shrub, hedge, screen or espalier. In locations such as St. Louis where it is considered invasive, gardeners typically keep the specimen in a pot on decks, patios or other outdoor sitting areas. It can also be tended to indoors as a houseplant.
Watch for scale and aphids, but overall, there are no serious problems with insects or disease for Osmanthus species. Once established in ideal conditions, just sit back and enjoy the evergreen consistency and delightful aroma of any of these shrubs.