From Halopedia, the Halo wiki
Florus is a human crop used as an all-natural, non-glucose-based sweetener. The plant is characterized by a green stalk and slim leaves, which are intensely green on top with a shining emerald green underside. Florus in the one and only export of Florus Corp, a corporation based out of Sonata, an Outer colony world.
Sonata, with its rich blond soil, was the only human world where florus crops could be naturally grown. While the stalks of the plant—where the sweetener is taken from—had been studied and successfully synthesized, it still did not compare with the organically-grown florus from Florus Corp. Competing companies who sold synthesized florus simply could not compete with the real deal.
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