There's a new cash crop on the horizon: stevia. This South American plant, which is 300 times sweeter than sugar but contains no calories, has become an increasingly popular alternative since the FDA approved its use in 2008. Now more and more farmers are abandoning some of their usual crops and growing stevia instead. The biggest transition, according to recent reports from Bloomberg and ABC News, is the tobacco industry, which sees big profits in the leafy greens.

This is a big change, since until now 85 percent of the stevia used in the U.S. was grown in other countries. But tobacco use is down in the U.S. — the world market for tobacco farming has shrunk 3.4 percent since 2008 — and struggling farmers are looking for alternatives. Stevia is a good option. As Bloomberg reports, tobacco and stevia plants grow in similar climates and soils. They're also cultivated the same way: leaves for each plant are picked and then dried before processing. One ex-tobacco farmer told Bloomberg that he can use the same machines and barns for stevia and the crop grows without pesticides, since the local bugs aren't attracted to the stevia plants.

This represents a big transition in a short amount of time. The first commercial stevia crop was only planted in the U.S. three years ago.

A lot of businesses are expecting big things from stevia. One manufacturer, Stevia First Corp., told Bloomberg that it expects the new sweetener to capture as much as a third of the $58 billion global sweetener market (sales are currently about $1 billion). Stevia First didn't mention the timeline under which they think that might occur under, but investors are salivating over the prospects. A recent article from the business site Smallcap Network predicted that the stock prices for Stevia First and other companies would rise quickly as the market for stevia expands. (Some of the other companies that could see big profits come from China, where the market is more firmly established.)

And it's not just U.S. farmers who are switching to stevia. Many farmers in Kenya have also started cultivating the crop with the assistance of another manufacturer, PureCircle. The company told Voice of America this summer that it has provided $1 million in micro-financing, as well as a team of experts, to help African farmers get started growing the plants. The push is expected to help raise the income for hundreds of farmers in Kenya and other countries.

Meanwhile, some people are actually growing their own stevia at home. The website offers tips on how to start and care for stevia plants indoors.

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