The heady scent of gardenias have filled gardens and graced corsages for years. Their creamy white, fragrant petals brighten up the garden, making gardenias an excellent foundation shrub, container plant or border specimen. Growing gardenias requires full to partial shade, a medium amount of water, and soil pH between 5.0 and 6.5. If the pH gets above 7.0, your shrubs will constantly battle iron and other mineral deficiencies. According to the University of Florida Extension Service, British naturalist John Ellis received a gardenia specimen in 1761 from China and named it after Dr. Alexander Garden, a botanist in Charleston, South Carolina.
Gardenia augusta, also called the cape jasmine, is native to southern China, Japan and Taiwan. It grows 6 to 8 feet high and wide with dark to bright green, glossy and leathery leaves. Gardenia augusta blooms for a long time, from mid-spring to early summer. Its heavily scented flowers are a waxy white, turning creamy yellow before dropping off. The 'Mystery' cultivar has deep green foliage and extremely large flowers. Gardenia augusta grows in U.S. Department of Agriculture Plant Hardiness zones 8 to 10.
Gardenia jasminoides 'Radicans' is a miniature shrub with intensely fragrant, double white flowers. Blooms cover its dark green foliage, which grows to 4 feet tall, in spring and fall. The 'Prostrata' cultivar grows only 2 to 3 feet tall but has a wider spread. Miniature gardenias require moist, well-drained acidic soil and full to part sun. The smaller cultivars can be used as a ground cover and in containers as well as a shrub specimen. They grow in USDA zones 7b to 11.
Gardenia thunbergia is a white gardenia native to South Africa. This spring-blooming shrub, which can grow to 10 feet, is often called the star gardenia. Its single, white flowers have a yellow center. The drought-tolerant thunbergia requries full sun and acidic soil. It grows in USDA zones 10a to 11.