Stevia has a been used for more than 1500 years by the native Indians of Paraguay and Brazil, they called it for “sweet herb” and used for sweetening their tea and also as an herbal medicine.
Around the world Stevia is believed to have many health benefits, practitioners of Thai Traditional medicine have started to use the plant, as well as it is used in many herbal recipes ex. It is used as a sweetener in herbal toothpaste.
In 1899 the Italian botanist Mosè Giacomo Bertoni observed the sweet taste of the plant Stevia and was European botanist to classify stevia. At that time Stevia has been known for a long time by the locals so it would, in my opinion, not be right to give him credit for discovering Stevia.
Since Bertoni first wrote about Stevia it has been widely spread around the world, I do not know for how long time it has been cultivated in Thailand but it has to be for some years.
I visited some years ago very big areas in the mountains north of Chiang Mai where they grow a lot of Stevia rebaudiana.
They told me when Coca-Cola in Japan started to buy, then from one year to the next, the price doubled.
Botanical name: Stevia rebaudiana
English name: candy leaf, sweetleaf, or sugar leaf.
Thai name: หญ้าหวาน “yaa waan”
Species: S. rebaudiana
Flower: Small white flowers in clusters<
Stevia is perennial shrub grows up to 80 cm.
Origin: South America
Range: S. America – Brazil, Paraguay and south-east Asia
Habitat: Ranging from grassland to mountain terrain.
Care: Grow best in full sun with a little shade in the afternoon, in rich soil.