Above is a hibiscus with a dark heart like the one painted in the article below.  Below you will see another photo of hibiscuses with no dark hearts.

IN BLOOM

Fuyo (Rose-mallow or Cotton rose)

By LINDA INOKI

Round the deserted mansion Hens take their ease, Rose-mallows are blooming.

By Masaoka Shiki (1866-1902)

This autumn haiku creates a peaceful picture of nature reclaiming its own. For centuries people have grown these shrubs (Hibiscus mutabilis) for their large, attractive flowers. They bloom from late summer until the first days of winter are near. Unusually, the flowers change color — starting pure white and then turning to clear pink before finally turning a deep purplish-pink after about three days. In China and Korea, the blooms are valued as herbs, and they are used in infusions or added to various foods. Hibiscus plants are members of the large Malvaceae, or mallow family of plants. Typical of the family, the flowers’ many stamens are fused together in a central tube. The leaves are large and woolly as are the sepals that enclose the flower buds. This rough surface helps to protect the plant from predators and also preserves moisture, so that the shrubs can survive periods of drought. In warm climates, the shrubs can grow to a height of 4 meters. Although this hibiscus is originally from southern China, it has become popular in the southern states of America. There, the fluffy seed heads remind people of another famous member of the mallow family, Gossypium spp., otherwise known as the cotton plant. And although it is not a rose, and neither from Dixie, Americans have affectionately named this Oriental shrub the Cotton — or Confederate — Rose.