Where is the Rose of Sharon(Hibiscus tree) native to?

The hardy Hibiscus syriacus are good to zone 5 but young plants will need shelter until established. This plant blooms in summer so should be pruned in late winter or early spring. Frequent severe pruning gives fewer but larger flowers; no or little pruning gives many small flowers. Personally I prefer the larger flowers and a smaller shrub. I remove 1/3 of the stems from an old established plant every year. The growth is late. The hibiscus and the locust both leaf out late.

http://treesandshrubs.about.com/od/commonshrubs/p/...

http://www.trop-hibiscus.com/gindr.html

East Texas Bald Cypress, Bur Oak, chinese language Pistachio, Chinkapin Oak, Deciduous Yaupon Holly, eastern crimson Cedar, Eldarica Pine, Eve's Necklace, Ginkgo, Lacebark Elm, stay Oak, Mexican Plum, crimson Oak, Scarlet Buckeye, Texas Ash, and Yaupon Holly.

They are native to Asia, and they usually don't need any special care through the winter.

china and india. zone 5 - 8. may be killed back in winter, but will come back