the spikes of flowers are bright gentian blue - an unusual color in the tropics. The flowers appear from green-and-white veined bracts that remain after the blooms fall, forming a column several inches long. The hairy leaves are large and dark green. ( wikipedia)
Light shade is preferred in a garden; in a greenhouse it needs warm conditions.
Blue Eranthemum, or Blue Sage is a strongly branched shrub, popular with gardeners in tropical India and China.