Winter Hardiness and Spring Regrowth of Four Varieties of Stevia rebaudiana (Bertoni) in Eastern North Carolina

Abstract

Stevia (Stevia rebaudiana) is attracting attention in the United States in response to consumer demand for healthier low-calorie sweeteners. Farmers are looking at stevia as a valuable alternative crop to add to their rotations not only for its high value but because it is perennial and can be repeatedly harvested reducing annual establishment costs. S&W Seed Company is testing stevia varieties across the southeastern United States at locations in North and South Carolina, Georgia, and Alabama. This study evaluated four stevia varieties grown at two locations near Nashville and Roseboro in North Carolina. S&W is focused on developing cultivars suited to the climate of the southeastern United States. Research was conducted for eight months in fields near Nashville and Roseboro North Carolina to assess winter survival, spring regrowth, and leaf-to-stem ratio of four top performing varieties in plots contracted by S&W with local farmers. All four varieties overwintered without significant winter kill and spring regrowth began from crowns in April and May. Weed interference in the Nashville location negatively affected percentage of regrowth in the spring. In Roseboro with lower weed pressure, regrowth occurred a month earlier with increases of 43% for SW-1005, 50% for SW-2267, and 114% for SW-2647. SW-2427 had no difference in percentage of survival between locations. Plants in Roseboro had greater mean plant heights and leaves per stem count. Stevia can be grown as an alternative perennial crop in coastal Carolina although there was significant winter die back and spring regrowth was slow.