The two hibiscus most commonly grown as annuals are not true annuals, but tropical shrubs that thrive outdoors during hot South Carolina summers. They can be grown in the ground or as container plants that are easily transported inside for the winter.

Chinese Hibiscus: (Hibiscus rosa-sinensis) is a tropical shrub that is often grown outdoors in the summer and as a houseplant in winter. It is not hardy in any part of South Carolina, but can be brought inside to a bright, sunlit area for the winter and planted out each spring. Chinese hibiscus are ideal for use as seasonal container plants.

The flowers are available in many colors, ranging through the entire spectrum except blue. The yellow, apricot and orange varieties provide colors not seen in hardy perennial hibiscus. Flowers are typically four to eight inches wide, and may be single or double.

Plant Chinese hibiscus outside after all danger of frost is past. Be sure to acclimate plants gradually to the increased light and lower temperatures outside. They prefer rich, well drained soil with plenty of organic matter, in full sun or light afternoon shade. Water the plants freely during the growing season, and fertilize with either a time release fertilizer every eight weeks or with a water soluble fertilizer every two weeks. To keep mature plants growing vigorously prune old wood back by about one third in spring.

Bring Chinese hibiscus indoors when nighttime temperatures fall into the lower 50s F.

Red Leaf Hibiscus: (Hibiscus acetosella) is most commonly seen in the cultivar ‘Red Shield’. This hibiscus is a tropical shrub, grown as an annual for the beauty of its deep burgundy red, maple like leaves. It can reach five feet tall by the end of summer. Purple flowers may appear late in the growing season. Plant outside after danger of spring frost, in full sun in well drained, moist garden soil. Propagation is mainly through seed planted in the spring.

Flower of an Hour: (Hibiscus trionum) is a true annual that is more a curiosity than a truly ornamental plant. It grows about two feet tall, with two inch wide, white to pale yellow blooms with dark centers. The flowers close in shade and typically bloom for only a fraction of a day. It is easily grown from seed, and may self-sow and return each year, sometimes to the point of weediness.