Species Native to Missouri
Common Name: evolvulus
Type: Herbaceous perennial
Family: Convolvulaceae
Native Range: Northern and western United States
Zone: 4 to 10
Height: 1.00 to 1.50 feet
Spread: 1.00 to 1.50 feet
Bloom Time: June to frost
Bloom Description: Lavender to blue
Sun: Full sun to part shade
Water: Medium
Maintenance: Low
Suggested Use: Annual, Ground Cover
Flower: Showy
Culture
This species is winter hardy to USDA Zone 4. It is easily grown in organically rich, consistently moist, well-drained soils in full sun to part shade. Performs well in sandy soils with good drainage. Plants may be difficult to find in commerce.
Noteworthy Characteristics
Evolvulus nuttallianus is native from Montana and North Dakota south to Texas and Arizona. In Missouri, it is found on limestone glades and bald knobs in the Ozark region of the State (Steyermark). It is a non-vining morning glory-like perennial that grows as a densely hairy subshrub to 20” tall with prostrate to decumbent stems that root at the nodes as they go. Features very small, bell-shaped, lavender to blue morning glories (to 1/2” across) from spring to mid-summer on stems clad with oblanceolate, hairy, silvery-green leaves (to 1” long). Flowers usually close up at night and on cloudy days. It must be noted that there is considerable confusion in the taxonomy of the genus Evolvulus. The within native species is sometimes listed as synonymous with E. pilosus (e.g., see Stemermark).
Genus name comes from the Latin word evolvo meaning "to untwist or unravel" because members of this genus, unlike many others in the Convolvulaceae family, do not twine.
Specific epithet honors British botanist Thomas Nuttall (1786-1839) who traveled extensively in the U.S.
Problems
No known serious insect or disease problems.
Uses
Best for rock gardens or native plant gardens.