Here's my speciosum:
Stats: 7-footer, pot diameter is 40cm. Grown from seedling (4 inches tall) in 2003 and yet to flower. Consistently doubled in size every year. What you see is half of the existing plant, because I split it in two when one of the centre canes rotted. Grown in full sun with Papilionanthe and Arundina, watered daily. Potting media: charcoal and large polystyrene pieces. Fed a lot with organic fert.