Culture
In its native range Exacum affine is an annual or short-lived perennial and is suitable for permanent outdoor cultivation only in humid tropical and subtropical areas. Grown as a pot plant, this plant requires a well-drained, but moist potting mix. Exacum will tolerate good light but not direct sun. Grow warm with 60° to 70°F night temperatures. They flower for an extended period, but are very difficult to keep growing after flowering, but cuttings can be taken successfully.
Noteworthy Characteristics
Exacum affine, commonly called Persian violet, is a 6 to 12 inch tall annual that is popular for its beautiful blue flowers and shiny green foliage. The tiny leaves of this rounded plant are ovate in shape and densely cover the stems. Lovely blue flowers with bright yellow pollen masses in their centers appear in the spring and summer. These fragrant flowers will densely clothe this plant if it is grown under the proper cultural conditions.
Genus name is a variant of the Gallic name exacon for centaurium transferred to this genus.
Specific epithet means related to or similar.
Problems
None serious. For more information see: Problems Common to Many Indoor Plants
Uses
In zones 10 to 12, Persian violet is used as a bedding plant or ground cover. In the St. Louis area, it is grown as a florist’s potted plant or used as a component of a container garden on a patio or deck.