Growing Zone of Lisianthus

Growing Zones

• Lisianthus is well-adapted for growing in all USDA zones, cites the University of Florida Extension. The planting times for various zones differ. For zone 7, the recommended planting time is June and July; for zone 8, the flowers are best planted in May, June and July; for zone 9, plant in April and May; and in zones 10 and 11, plant during March, April, October and November.

Plant Description

• The upright plants have a mature height of about 1 to 2 feet with a ½- to 1-foot spread. The ovate, simple leaves are opposite and 2 to 4 inches long. The flowers bloom in shades of purple, lilac, pink or white. New varieties contain other shades and bi-colors. The pointed flower buds are swirled and unfurl into large, single or double, goblet- shape flowers with curling tips. Dwarf plants are also available.

Cultural Requirements

• Lisianthus grow best in areas of full to partial sun and adapt well to a variety of fertile soil types including acidic, clay, sand, loam and slightly alkaline. The plants are moderately tolerant of drought. Lisianthus is poorly tolerant of frost and is highly susceptible to fungal disorders, a trait that has greatly limited its use in home gardens. Propagation from seed is very difficult as seeds have slow germination rate. Space plants 6 to 12 inches apart.

Uses

• The long-lasting flowers of lisianthus are used primarily as cut flowers for floral arrangement. In "Garden to Vase," Linda Beutler and Allan Mandell describe lisianthus blooms as exemplary cut flowers that are not only long-lasting and highly attractive but are also available throughout the year. For floral arrangements, harvest after two florets per stem have opened with well-developed color. Cut stems stay fresh for up to two weeks in water.