Common Name: montbretia
Type: Bulb
Family: Iridaceae
Native Range: Temperate southern Africa
Zone: 6 to 9
Height: 2.00 to 3.00 feet
Spread: 1.00 to 1.50 feet
Bloom Time: July to August
Bloom Description: Orange
Sun: Full sun to part shade
Water: Medium
Maintenance: Medium
Flower: Showy
Culture
Best grown in moist, organically rich, slightly acidic, moderately fertile, well-drained soil in full sun to part shade. Prefers full sun in cool summer climates, but appreciates some part afternoon shade in hot summer climates such as the St. Louis area. Plant corms in spring after last frost date approximately 3-4” deep and 6” apart. In optimum growing conditions, plants will spread over time (stoloniferous corms) to form colonies. Plants may be propagated by division or removal of offsets. These plants are not reliably winter hardy throughout USDA Zone 5 where they will benefit from being sited in protected locations (e.g., near the south side of a house) and mulched in winter. To avoid risk of loss in Zone 5, corms may be lifted in fall, dried and then stored for winter in a dry medium in a cool but frost-free location.
Noteworthy Characteristics
Crocosmia pottsii is a cormous perennial that is native to moist grasslands and stream banks in South Africa (Natal and Transvaal). It is a clump-forming plant that grows 2-3’ tall. It is noted for its erect, sword-shaped, medium green, basal leaves (to 18-24” long) and deep orange flowers (to 1.25” long) that are sometimes flushed with red. Flowers appear in summer above the foliage on the upper portions of wiry, arching, branched scapes. This species is not commonly found in commerce, but it is one of the parents of the popular Crocosmia x crocosmiiflora hybrids sold under the common name of montbretia.
Genus name comes from the Greek words krokos meaning saffron and osme meaning a smell for the smell of dried flowers steeped in warm water.
Specific epithet honors John Potts (d. 1822) or C.H. Potts (fl.1877).
Problems
Spider mites can cause significant damage to the foliage, and, if left unchecked, can impair normal flowering. Winter hardiness is a concern in the St. Louis area.
Uses
Perennial borders. Also effective in containers where lifting corms for winter is rather simple.