The Tea Olive (Osmanthus fragrans) is an evergreen shrub or small tree celebrated for its intensely sweet, apricot-like fragrance. Native to Asia, it is a popular feature in warm-climate landscapes due to its year-round foliage and seasonal aromatic flowers. Understanding the full growth potential of the Tea Olive is necessary for successful long-term gardening and landscape design. The mature size of any given specimen can vary significantly, making it essential to know the expected size range and the variables that affect its growth.
Typical Mature Dimensions of Tea Olive
The common species, Osmanthus fragrans, generally develops into a large shrub or small tree. In cultivation, the plant typically reaches a height of 10 to 15 feet, though in optimal conditions, it can mature to heights between 20 and 30 feet. The lateral spread for a fully mature specimen commonly falls between 8 and 20 feet, creating a broad, dense canopy. The Tea Olive has a slow to moderate growth rate, typically adding 4 to 12 inches of new growth annually, meaning it often takes a decade or more to reach its full size.
Factors That Influence Overall Size
A Tea Olive’s genetic potential for height and width is heavily influenced by the conditions of its planting site.
Climate and Soil
Climate plays a significant role, with plants grown in the warmest parts of their range (USDA Hardiness Zones 8b through 11) achieving the largest dimensions. Cooler regions may limit the ultimate size, sometimes causing the plant to remain a smaller, denser shrub. Soil quality also affects the plant’s vigor. Rich, well-drained soil provides the resources necessary for it to reach the upper end of its size potential, and consistent moisture supports a robust root system.
Sun Exposure
The amount of sun exposure dictates the density and shape of the mature canopy. Full sun encourages a compact, dense crown. Conversely, deep shade can lead to a thinner, more open growth habit. In areas with intense summer heat, providing some afternoon shade is recommended to prevent leaf scorch.
Size Variability Among Popular Cultivars
Gardeners often select named cultivars bred for specific growth habits when a size different from the species standard is required. For instance, the popular variety ‘Fudingzhu’ is known for its profuse flowering and moderate size, typically reaching 8 to 15 feet high with a 5 to 8-foot spread. This makes it a manageable choice for smaller gardens or foundation plantings.
Other varieties are selected for their compact nature, such as ‘Fragrant Princess’ (or ‘Kaori Hime’), which is a true dwarf form. This variety often stays within a compact size of 2 to 4 feet tall and wide. Similarly, the ‘Ogon’ cultivar, often a form of Osmanthus heterophyllus, typically reaches 4 to 8 feet in both height and width.
Managing Size Through Pruning and Placement
Controlling the size of a Tea Olive begins with proper placement in the landscape. Planting the shrub with adequate space to accommodate its mature size minimizes the future need for aggressive pruning. For screens or hedges, spacing specimens 5 to 10 feet apart allows air circulation and prevents overcrowding.
To maintain size and shape, selective thinning is the preferred pruning method, which involves removing entire branches back to a main stem to preserve the plant’s natural form. Hard shearing is discouraged because it reduces the bloom display, as flowers appear on old wood. Pruning is best performed immediately after the main flowering period, typically in late winter or early spring.