There are numerous species of Camellia (about 250) but the Camellia types commonly grown as landscape shrubs are Camellia sasanqua, Camellia japonica, and hybrids of these.
Camellia x williamsii are the first camellia hybrids. Generally blooming after the Japanese camellias, they result from the cross of Camellia japonica and Camellia saluenensis. Among the most cold-hardy camellias (inherited from the japonica parent), most of them are extremely vigorous, free-blooming, with attractive, semi-glossy, leathery leaves.
- Graceful shrubs, they tolerate low light intensity and bloom over a long season, providing a spectacular show. They drop their spent heads with elegance (no deadheading required!), leaving a tidy bush. They enjoy a wide range of habits, from dwarf to large and spreading.
- Camellia x williamsii are regarded as the best camellias for general gardening. Highly reliable, they enjoy an exceptionally long flowering period. Some varieties such as 'November Pink' and 'St Ewe' flower over 4 or 5 months from well before mid winter through until mid spring. The sheer floriferousness of x williamsii camellias and their upright growing habit makes them a more attractive garden plant than the older Camellia japonica varieties.
- The evergreen foliage of these hybrid camellias is usually similar to that of Japanese camellias, but their leaves are often narrower.
- Part shade lovers, Camellia x williamsii are best grown in consistently moist, acidic, organically rich, well-drained soils. Apply a root mulch (leaves or shredded bark) and provide a site sheltered from cold, dry winds as buds and flowers may be damaged by cold winds. Protect from early morning sun and from direct hot summer afternoon sun. Older camellia plants can thrive in full sun when they are mature enough to have their roots shaded by a dense canopy of leaves.