A species found in the north of Vietnam through to the provinces of Guangdong and Hainan in China, as well as the territory of Hong Kong.
Its leaves are 4 in /10 cm long ,the showy flowers grow singly on 8 -in /20 -cm -long ,the showy flowers grow singly on 8-in/20 -cm-long spikes and they are faithful to their species name - their predominant color is purple in different shades . The plant blooms between June and August .