Answer: Hibiscus mutabilis is an old-fashioned perennial or shrub hibiscus better known as the Confederate rose. It tends to be shrubby or treelike in Zones 9 and 10, though it behaves more like a perennial further north. Flowers are double and are 4 to 6 inches in diameter; they open white or pink, and change to deep red by evening. The 'Rubra' variety has red flowers. Bloom season usually lasts from summer through fall. Propagation by cuttings root easiest in early spring, but cuttings can be taken at almost any time. When it does not freeze, the Confederate rose can reach heights of 12 to 15 feet with a woody trunk; however, a multi-trunk bush 6 to 8 feet tall is more typical. Once a very common plant throughout the South, Confederate rose is an interesting and attractive plant that grows in full sun or partial shade, and prefers rich, well-drained soil.
Hibiscus coccineus is better known as the Texas Star Hibiscus. It has large, single, red flowers about 3 to 4 inches in diameter that appear atop branches of palmately lobed leaves with three to seven segments. Culture is very easy, with well-drained soil, an annual application of fertilizer in spring or early summer, and a sunny location being most important. Texas Star Hibiscus may be propagated from seed or cuttings. Mulching the plants in wintertime prevents root injury during very cold weather. Old stems, if they freeze, should be pruned back to the ground in early spring. Even if frost damage has not occurred, it is still a good idea to prune back and shape the plants before growth begins.
Best wishes with your landscape!
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