Native to the Carolina forests, most perennial Hibiscus are rated a USDA zone 4 for winter hardiness and down to a warm zone 9 for summer heat tolerance.
They are typically July-August bloomers although a few bloom later than this. If grown in good rich soil, this plant will quickly turn into a four to six foot tall bush every spring (dying to the ground over winter). The flowers will also be amazingly large at six inches across.
They are usually pruned to the ground in the fall and regrow (starting as one of the last perennials to emerge) each spring.
This wonderful plant, if grown in a moist, rich soil in full sun or part shade can easily hit 4 to 6 feet tall in a season and be covered by a delightful display of huge six inch blooms in late summer.