Rose of Sharon. Large 5-6" single lavender flowers with a lacy center from July thru September. Tall 8-12' - Plant 5' apart zone 5-9. Very useful for the late summer to early fall bloom. It is slow to begin growing in the spring but makes up for lost time fast. Hibiscus has been popular for nearly 200 years and with good reason. Its size and growth habit allow it to be planted near a home or in a border, and its flowers are spectacular.