The main producers of stevia are Japan, China, Taiwan, Thailand, Korea, Brazil, Malaysia and Paraguay. This is based on the suspicion that a derivative of stevioside may be harmful to humans. Stevia rebaudiana from the Asteraceae family was re-discovered by MS Bertoni in 1888. It is a short day plant, growing up to 0.6 meters in the wild and flowering from January to March in the southern hemisphere. Flowering under short day conditions should occur 54-104 days following transplanting, depending on the daylength sensitivity of the cultivar.
Stevia grows naturally on infertile, sandy acid soils with shallow water tables.
This is normally in areas like the edge of mashes and grassland communities. The natural climate is semi-humid subtropical with temperature extremes from 21 to 43 C, averaging 24 C. Stevia grows in areas with up to 1375mm of rain a year. The sweet stevia compounds vary in concentration with the method of propagation, daylength and agronomic practices. Reproduction in the wild is mainly by seed, but seed viability is very poor and highly variable. Some of the biggest production constraints in Australia are extreme radiation, low water availability, Australian landrace stock and general agronomic information to suit the local environment.