Alpinia purpurata aka Red Ginger

Alpinia purpurata, or red ginger, is in the ginger family. The family's name is Zingiberaceae. Its native range spans Maluku to the southwest Pacific. It includes New Guinea and the Solomon Islands. New Caledonia and Vanuatu also lie in this range. It grows in wet, tropical lands, in disturbed forest and old gardens. It also grows by trails and streams. Wild plants grow up to about 1,640 feet [500 metres] above sea level.

This plant is an evergreen perennial: it keeps its leaves and lives for years. It forms clumps from a rhizome, a creeping stem below ground. Its leafy stems stand upright. The RHS lists a garden height of 8–13 feet [2.5–4 metres]. Chicago Botanic Garden lists a shorter height: 6 feet [1.8 metres]. Clumps spread about 1.6–3.3 feet [0.5–1 metre] wide. The long, pointed green leaves have a slight gloss. They reach about 2.6 feet [0.8 metres] long. Plants take about two to five years to reach full size.

Long flower spikes rise above the leaves, though not fully upright. Small white flowers sit among bright red bracts. These leaf-like parts overlap and give the spikes most of their colour. Chicago Botanic Garden also lists pink and lavender blooms. The RHS records blooms in summer. Tropical sources report blooms all year. Bees, butterflies and birds seek nectar in the flowers. Growers raise this tropical plant for show and cut flowers. Its bold leaves suit use as a stand-alone plant. They also suit glasshouses, including conservatories.

Give it rich, moist soil that drains well. The RHS calls for neutral loam and bright light screened from direct sun. Other sources allow light shade, or full sun to partial shade. Under glass, use peat-free compost based on loam. Add leaf mould and composted bark. Give the clump room to grow freely. Water well while it grows, then give less in winter. Keep winter heat at or above 16°C. The RHS rates it H1A; Chicago lists USDA zones 10–11.

The RHS reports few pest or disease problems. In spring, cut out stems that have finished blooming. To grow more, divide clumps in spring. Or sow fresh seed at 20°C. Take care where escaped plants could spread into nearby habitats. This species has become invasive on Pacific islands, including Fiji and Hawaii. Useful Tropical Plants lists no known food uses or hazards. It records folk use of fruit for sores. It also records use of boiled leaves for stomach complaints. These reports do not prove that such medical use is safe or works.