Culture
Winter hardy to USDA Zone 10-11 where plants are best grown in rich, consistently moist, well-drained soils in full sun. Tolerates part shade. Consider raised beds as a way to create sharp drainage. Thrives in sandy loams. Avoid overwatering which may encourage the onset of root rot. Root mulch helps retain soil moisture in hot summer climates. In St. Louis, sweetleaf can be grown as an annual. Purchase starter plants if available. Seed (if obtainable) can be started indoors in early spring for planting outside after last spring frost date. Plants may be grown in pots set out on patios during the growing season. Snip off flower buds as they appear (best quality leaves occur prior to flowering). Harvest leaves in fall. If overwintering, bring pots indoors before first fall frost. Cutting may be taken.
Noteworthy Characteristics
Stevia rebaudiana, commonly known as sweetleaf, is a tender perennial herb that is native to Paraguay and Brazil. Plants typically grow with weak and floppy stems to 12-24" tall. Plants have little ornamental attraction. The attraction here is the sweet tasting leaves which contain glucoside compounds that are 200-300 times sweeter by weight than cane sugar but with no calories. To date, the FDA has only approved limited use for this plant in the U.S. (Rebaudioside A approved as dietary supplement but stevia leaves are not approved as food additive), but its potential as a sugar-substitute is huge. Slender oblong leaves (to 1") have a pronounced midrib. Tubular flowers are white with no fragrance. Harvest fresh leaves for use in teas. Eat leaves directly off the plant. Leaves may be dried and then saved in jars for future use. Dried leaves are generally sweeter than fresh leaves. Dried leaves may be ground up in a blender into stevia powder.
Genus name honors Pedro Jaime Esteve (d. 1566) of Valencia, Spanish botanist and physician.
Problems
No serious insect or disease problems.
Uses
Annual for herb garden. Window box or clay pot.