If there is one plant the symbolises the tropics, that plant would most likely be Hibiscus. This flowering shrub has spread throughout South East Asia and the tropical world in its many variant and hybrid forms.
Generally considered as 'the most well known' form of Hibiscus, H.rosa sinensis has an entire range of flower sizes and colour varieties; with some species able to grow to up to 5 metres in height. The colours are just as unpredicable, coming in a whole rainbow scale from pure white, reds, pinks, to hues of lemony yellow.
Hibiscus require full sun to flower well, and can be pruned into hedge form.