1 Costus comosus

Costus comosus var. bakeri.

Costus comosus, Red Tower ginger was previously known as Costus barbatus.
The clump forming herbaceous perennial plants are up to 2 m high.
The thin cane-like stems grow from underground rhizomes.
The stems twist in a spiral.

The alternately arranged narrowly elliptic leaves are up to around 40 cm long by 10 cm wide.
There are long soft hairs on the lower surface.
There is no petiole and the base of the blade forms a closed sheath down the stem.
The green membranous ligule, and the top of the sheath both have long fine hairs.

The terminal inflorescences are conical spikes.
The overlapping, waxy red spirally arranged bracts curve down slightly.
Each bract holds 1 tubular yellow flower.
The flowers, around 4 cm long only open a few mms across at the tip.

The 3 sepals, around 3 cm long are mostly fused into a tube with lobes only a few mms long.
The 3 separate petals are slightly longer than the sepals.
The single fertile stamen has a wide petal-like filament around 3.5 cm long.
The anther, around 7 mm long has 2 pollen sacs that open inwards through longitudinal slits to release white pollen.

The 5 staminodes are fused into a labellum with irregular small teeth on the edge.
The base of the labellum is fused to the base of the stamen filament.

J.F.