Cultivar is a contraction of "cultivated variety". Cultivars are plants that have been intentionally bred to have certain characteristics, like purple foliage or more petals. Cultivars don't occur naturally.
Cultivars usually do not grow true from seed and will need to be propagated by some means other than seed, like grafting, cuttings or repeated hybridization. However they are only considered a cultivar if the distinguishing characteristics that make them unique from the original plants are retained when they are propagated.
Cultivar names are not italicized. They appear after the species name and are enclosed in single quotes, for example: Solanum lycopersicum 'Red cherry'. (Older nomenclature sometimes designated cultivars by preceding the name with the abbreviation cv.). As opposed to varieties where the variety is shown fully italicized, for example: Beta vulgaris subsp. vulgaris var. vulgaris
- Iannotti, M.(2009). Gardening Question of the Week: What’s the Difference Between a Variety and a Cultivar?. About.com:Gardening. Retrieved: 2010-09-13.