In the human history of the Hawaiian Islands, no plant has had greater significance than kalo. It sustained kingdoms for centuries and enabled the initial population of Polynesian explorers to grow to by some estimates as many as a million people. Kalo was farmed across the Islands in numerous ways, says enthobotanist Dr. Kāwika Winter.
“At the height of cultivation they were planting kalo from the shoreline all the way up as far as humans were existing and there’s all these different methods of planting: If you’re in a forest, if you’re in a lava field or if you’re in an area where there’s streams.”
You can break kalo cultivation up into two broad classes of farming: dryland, where the kalo is not flooded, and wetland, where it is.
“Ultimately the method that seems to have been the most productive and the most high-yielding was growing the kalo under irrigated pond fields called lo‘i.”
Lo‘i kalo filled with fluttering emerald green leaves stretched far and wide across Hawai‘i, offering endless sustenance, great beauty and evidence of tremendous ingenuity.
“The trick to growing healthy kalo is you have to have cool water, the trick to having cool water is you have to engineer your whole field system such that the circulation is constant, such that the water gets back to the cold source whether it’s the irrigation ditch or the stream. So the engineering behind these field systems was quite spectacular.”