maybe medinilla is called by another name in another place so i decided to attach a photo of a medinilla flower i had last year. the flowers lasted for about 4 months, very pretty. i followed instructions written in the label. it was written that it can flower again anytime during the year but it hasn't flowered again for a year now. somebody out there might have had experience caring for a medinilla.
If you haven't already done so, you could try looking for information using the botanical name Medinilla magnifica. According to my plant books this plant prefers a warm, greenhouse environment with higher humidity levels.