Stevia plants do best in full sun and a rich, loamy soil.  Wait to plant Stevia until the soil is warm.  Plant at the same level as the soil in the pot.
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                  Water only when needed being careful not to overwater.  Use a lower Nitrogen fertilizer. 
               
              
                  Harvesting should be done as late as possible, since cool autumn temperatures and shorter days tend to intensify the sweetness of the plants.