Dichorisandra thyrsiflora aka Blue Ginger

Dichorisandra thyrsiflora is an evergreen perennial known as blue ginger. It belongs to the spiderwort family, not the ginger family. Its fleshy stems and upright shape give it a ginger-like look. It comes from eastern Brazil, including Bahia, Minas Gerais, and Rio de Janeiro. Kew places it in a tropical region with seasonal drought. Gardeners grow it for its blue blooms and glossy leaves.

The plant forms upright clumps from underground rhizomes. In good growing conditions, these can spread into colonies. Garden plants often reach 3–6 feet (0.91–1.83 m) tall. Missouri Botanical Garden notes occasional heights of 8 feet (2.44 m). RHS gives an upper height of about 8.2 feet (2.5 m). Missouri lists a spread of 3 feet (0.91 m). The cane-like stems have spots and carry leaves in a spiral. Each leaf has a sheath that wraps around the stem. The dark green leaves are glossy and shaped like lances. They reach about 0.7–1 foot (0.2–0.3 m) long. They extend outward from the stems, giving the clump a leafy outline.

Blue to deep violet flowers form dense clusters at stem tips. Each bloom has three petals, yellow stamens, and a white centre. Flower clusters reach about 0.7 feet (0.2 m) long. Missouri reports flowering most often from June to October. RHS describes autumn bloom, while Chicago lists bloom across the year. The season therefore varies between the sources. Chicago also reports that the plant attracts butterflies. Its blooms make it useful as a border or specimen plant. Groups can bring blue colour to a sheltered tropical garden.

Grow it in moist, rich soil that drains well. Missouri recommends part shade and shelter from hot afternoon sun. RHS advises bright, filtered light for plants grown under glass. Both sources stress high humidity and a sheltered site. Strong winds can damage tall stems. Keep greenhouse soil moist during growth, with less water in winter. Missouri gives USDA zones 10–12 and warns of frost damage. RHS rates it H1B, allowing outdoor summer growth in Britain. Containers also suit indoor growth as a houseplant.

Mealybugs may cause trouble, though RHS reports few disease problems. Waterlogged soil can lead to root rot. RHS says the plant needs no routine pruning. Missouri allows cutting back stems once the flowers finish. Division and stem cuttings provide ways to raise new plants. Missouri also lists seed propagation.