At least three different species of gingers (Zingiber spp.) produce flowering structures that resemble pine cones. Botanically speaking, these cones are referred to as a type of cone-shaped inflorescence called a "strobilus." Overlapping rows of waxy bracts house the true tiny flowers, which last only a few days, but the colorful bracts persist for weeks or months. These gingers are all tropical, herbaceous plants suitable for growing outdoors in U.S. Department of Agriculture winter hardiness zone 9 and warmer.
Three gingers that produce the cone-like strobili structures are the beehive or pine cone ginger (Zingiber spectabile), wild or bitter ginger (Zingiber zerumbet) and the jewel pagoda (Zingiber neglectum). Each is seasonally dormant, even in the warm tropics. Dry conditions, mainly in the winter months, or "dry season," cause foliage to wither and reappear only when rainfall and warmth increase in spring or summer, the "rainy season."
These gingers are native to tropical southern Asia. Pine cone ginger hails from Malaysia and southern Thailand. Southern India and Sri Lanka are the likely native range of wild ginger, according to Kirsten Albrecht Llamas, author of "Tropical Flowering Plants." Wild ginger has been widely cultivated across tropical Asia to obscure its origins. Jewel pagoda is indigenous only to Indonesia's island of Java.
Each of these three gingers produces its strobili in the warm and rainy summer months. Hidden by the tall leafy stems, the flowering stalk emerges from the underground rhizome and grows only 12 to 20 inches tall. The tip on the stalk swells as it develops into the strobilus, forming cupped bracts in a loose to tightly bound cone-like structure. Pine cone ginger's bracts are golden yellow and then age to red; its true flowers are white with purple-brown and yellow spots. Wild ginger's bracts are green while the true pale yellow flowers appear. After the flowers drop, the bracts become bright red. Jewel pagoda's bracts are green as the flowers, which are true translucent white with purple spots, open. The curled bracts then turn red. In all these gingers, the strobili persist for months, gradually drying and then toppling over once the dry season dormancy begins.
Plant these gingers in a fertile sand or crumbly loam soil that is rich in organic matter. The soil must be well-draining. They need partial sun to partial shade conditions, such as that of shifting light under tall trees. Water and fertilize the plants freely from spring to fall, when foliage and flowers appear and are actively growing. Once foliage naturally begins to yellow and dry in late fall, cease fertilizing altogether, and taper off watering so that the plant rests dormant underground in dry soil conditions. The rhizomes are protected from winter frosts while underground or are further insulated with a thick layer of dry mulch. If winter temperatures regularly drop below the 15- to 20-degree Fahrenheit range, consider digging up rhizomes to overwinter indoors in a crate of shredded newspaper in a cool, dry place.
These gingers that produce the cone-like flowers make beautiful tropical accent plants in a mixed tropical border. As recommended by Kirsten Albrecht Llamas, consider planting them on a raised slope or atop a retaining wall for the best viewing of the short flower stalks under the plant leaves. They make excellent, long-lasting cut flowers for arrangements or bouquets, enduring about two weeks if water is exchanged daily in the vase.