Culture
Sub-tropical tender perennial that is winter hardy to USDA Zones 9-11. In St. Louis, it is best grown in the ground as an annual vine, but may also be grown in containers. It is easily grown in average, medium, well-drained soils in full sun. Appreciates some afternoon shade in hot summer climates. Start seed indoors in late winter (about 8-10 weeks before last frost date). Needs a substantial structure upon which to grow.
Noteworthy Characteristics
Cobaea scandens, commonly called cup and saucer vine, is native to Mexico and tropical South America. It is a vigorous, rapid-growing, tendril-climbing vine that typically grows to 30-40’ in its native habitat. When grown as an annual, it can grow 10-20’ in a single season. The descriptive common name is in reference to its bell-shaped flowers (cups), each of which is subtended by a saucer-like green calyx. Flowers last about 4 days, emerging green but maturing to purple. Flowers have a musky fragrance. Blooms late summer into fall. Pinnate leaves have four leaflets. Also commonly called cathedral bells. Flowers are reportedly pollinated by bats.
Genus name honors a Jesuit Father, Bernardo Cobo (1572-1659), Spanish missionary and naturalist in Mexico and Peru.
Specific epithet means climbing.
Problems
No serious insect or disease problems.
Uses
In the St. Louis area, this fast-growing annual vine provides quick cover for trellises, walls, fences, arbors or poles. Also may be grown in large containers.