Hylocereus undatus

H. undatus is a fast growing, epiphytic or xerophytic, vine-like cactus. Stems are triangular, 3-sided, although sometimes 4- or 5-sided, green, fleshy, jointed, many branched. Each stem segment has 3 flat wavy ribs and corneous margins may be spineless or have 1-3 small spines. Stems scandent, creeping, sprawling or clambering, up to 10 m long. Aerial roots, which are able to absorb water, are produced on the underside of stems and provide anchorage for stems on vertical surfaces. Flowers are 25-30 cm long, 15-17 cm wide, nocturnal, scented and hermaphroditic;however, some cultivars are self-compatible. Flowers are typically white in colour and bell shaped, stamens and lobed stigmas are cream coloured. Fruit is a fleshy berry, oblong to ovoid, up to 6-12 cm long, 4-9 cm thick, red with large bracteoles, pulp white, edible, embedded with many small black seeds. Average fruit weight is 350-400 g, although may weigh up to 900 g (Merten, 2002).