Bananas produce vegetative suckers at the base of the plant which can be removed and planted separately. Bananas are planted at a typical density of between 1500-2500 plants per square hectare. Between 9-14 months after planting, each plant produces some 20-40 kilograms of fruit. After the harvest, the plant is cut down, and one sucker is allowed to grow up to produce the next crop.
THE HISTORY OF THE BANANA
Bananas are difficult to study archaeologically, and so the domestication history was unknowable until recently. Banana pollen, seeds and pseudostem impressions are quite rare or absent at archaeological sites, and much of the recent research has been focused on the relatively new technologies associated with opal phytoliths, basically silicon copies of cells created by the plant itself.
Banana fruit ready to harvest
Banana phytoliths are uniquely shaped: they are volcaniform, shaped like little volcanoes with a flat crater at the top. There are differences in the phytoliths between varieties of bananas; but variations between wild and domesticated versions are not as yet definitive, so additional forms of research need to be used to fully understand banana domestication.
Genetics and linguistic studies also help in understanding banana history. Diploid and triploid forms of bananas have been identified, and their distribution throughout the world is a key piece of evidence. In addition, linguistic studies of local terms for bananas support the notion of the spread of the banana away from its point of origin: island southeast Asia.
Banana Domestication and Dispersal
In Oceania, the earliest unequivocal evidence for banana cultivation has been at the Kuk Swamp, in Papua New Guinea. Archaeological evidence from the Kuk Swamp of the highlands of New Guinea indicates that bananas were deliberately planted by at least as long ago as 6950-6440 cal BP (see footnote). Kuk Swamp, as its name implies, is located on a wetland margin, and its importance for understanding the development of agriculture in the region cannot be overstated. The earliest occupations at Kuk Swamp are dated to ~10,220-9910 cal BP, although whether these levels represent true agriculture is as yet uncertain.
An extensive network of ditches constructed for drainage and cultivation is in evidence in the Wahgi Valley as well, dated beginning ca 6000 BP and continuing up until AD 100. The ditches represent a long series of wetland reclamation and abandonment, where Kuk's residents struggled with developing a reliable agricultural method.
The oldest human occupations associated with agriculture at the swamp edge are pits, stake- and post-holes and man-made channels associated with levees near a paleo-channel. A paleochannel is a waterway that has since been abandoned, and charcoal from the channel and from a feature on the adjacent surface returned dates between 10,200-9910 cal BP. Scholars interpret this as evidence of planting, digging and tethering of plants in a cultivated plot.
This 2002 aerial photograph of the site of Kuk Swamp in the New Guinea highlands, was taken by NASA
Additional evidence indicates that the banana was dispersed out of New Guinea and introduced into eastern Africa and later into south Asia by 2500 cal BC, and probably earlier.Like coconuts, bananas were most widely spread as a result of the sea exploration of the Pacific by Lapita peoples, of extensive trade voyages throughout the Indian Ocean by Arab traders, and of exploration of the Americas by Europeans
Banana tree and fruit
Footnote: Before Present (BP) years is a time scale used in archaeology, geology, and other scientific disciplines to specify when events in the past occurred. Because the "present" time changes, standard practice is to use AD 1950 as the origin of the age scale, reflecting the fact that radiocarbon dating became practicable in the 1950s.