Common Name: hardy hibiscus
Type: Herbaceous perennial
Zone: 5 to 9
Height: 4.00 to 5.00 feet
Spread: 3.00 to 4.00 feet
Bloom Time: July to September
Bloom Description: Pink with dark red eye zones
Sun: Full sun
Water: Medium to wet
Suggested Use: Annual, Rain Garden
Tolerate: Deer, Wet Soil
Easily grown in average, medium to wet soils in full sun. Best in moist, organically rich soils, but does surprisingly well in average garden soils as long as those soils are not allowed to dry out. Regular deep watering is advisable. Tolerates some light shade, but full sun with good air circulation produces best flowers, strongest stems and the best environment for resisting potential diseases. Site in locations protected from wind to minimize risk of wind burn. Pinch back growing tips when they reach 8” and again at 12” if bushy plants are desired. Deadhead individual flowers to maintain plant appearance. Cut back stems to approximately 3-4 inches in late autumn. New growth shoots are slow to emerge in spring. However, once new growth begins, it proceeds quite rapidly and plants will benefit from regular fertilization during the growing season.
‘Sweet Caroline’ is a vigorous, sturdy, rounded, somewhat shrubby, woody-based hibiscus cultivar that typically grows to 4-5’ tall and features dinner plate-sized, 5-petaled, hollyhock-like flowers (to 6-8” diameter) which are among the largest flowers produced by any perennial which is hardy to the St. Louis area. Flowers are bright pink with darker veins and dark red eye zones. Overlapping flower petals are partly reflexed and slightly ruffled. Each flower has a prominent and showy creamy white to pale yellow central staminal column. Individual flowers last only one day, but one or more flowers usually open each day, in succession, over a long mid-summer to early fall bloom period. Oval dark green leaves. Plant patent #7608 issued July 30, 1991.
No serious insect or disease problems. Some susceptibility leaf spots, blights, rusts and canker. Japanese beetles, whiteflies and aphids are occasional insect visitors. Japanese beetles can severely damage foliage if left unchecked. Leaf scorch will occur if soils are allowed to dry out. Healthy plants grown in the proper environment usually do not need staking.
Borders. Specimen, group or mass for landscape accent. Temporary hedge. Useful in low spots or wet areas in the landscape. Effective along streams or ponds.