Following the December, 2016 United States Food and Drug Administration approval of Rebiana, a stevia-based sweetener, this little plant has seen a surge in popularity. Stevia rebaudiana, commonly known as sweetleaf or simply stevia, boasts lovely green foliage with a startlingly sweet kick.
Stevia extracts can be up to three-hundred times as sweet as sugar, but may have a bitter aftertaste. The fresh leaves of the plant deliver a respectable thirty times the sweetness of sugar, with a mild aftertaste often described as licorice-like.
Easily Grown From Cuttings
Stevia is easily grown in most areas of the United States. It can be grown as a perennial in areas with mild winters, and as an annual anywhere where temperatures remain above forty degrees through a growing season of at least three months.
Stevia seeds can be very difficult to germinate. Established cuttings, widely available on the Internet and through specialty nurseries, are a more practical solution for most home gardeners. These young plants are vulnerable to cold, and should not be transplanted into a garden or outdoor container until well after the last frost.
Stevia Likes Nutrient-Rich Soil and Lots of Room to Grow
Young plants should be spaced at least two feet apart, in full sun to partial shade. Stevia is a heavy feeder, and benefits from generous portions of compost worked into the soil prior to planting, and from monthly applications of compost or low-nitrogen fertilizer.
Once planted, stevia requires little in the way of special care. Plants should be watered lightly, and may wilt slightly during the hottest hours of the day. Excessive watering should be avoided, as it decreases the sweetness of the leaves and may cause the roots to rot.
Prune Tops as Necessary
When your plants are about a foot tall, they should begin to branch out and become bushier. If not, they can be encouraged to do so by topping. Simply use a sharp pair of scissors or garden clippers to remove the top of the plant, directly above the highest point where it branches.
As your plants mature, they will develop small, white flowers. Pretty though they are, these flowers should be pinched or cut off the plant before they blossom. Allowing flowers to bloom will slow the production of new foliage and can cause a strong, bitter aftertaste in the leaves.
Plants will grow to a height of two to three feet. Leaves may be harvested for fresh use throughout the growing season. In Autumn, before the first frost, the plants should be cut down, and the leaves stripped from the stems and dried for use through the winter.
In warmer climates, leave about six inches of healthy plant above the ground when you cut down your stevia. The plant can survive a few light frosts, but does not take well to snow or prolonged, extreme cold. If in doubt, take one or more three inch cuttings from the tops of your mature plants. Treated with rooting horomone, these will take root quickly and grow happily in a sunny window until spring.
Stevia leaves can be used fresh or dried. Dried leaves can be ground in a coffee grinder to make a very sweet powder, which can then be soaked in water to make a liquid sweetener. Fresh leaves have a pleasant, mild flavor that works well in teas and fruit-based dishes. While sweeter than sugar, stevia does not dissolve or caramelize, and is not appropriate in recipes where sugar is used for texture, as in many baked desserts.
Sources: Goettemoeller, Jeffrey. Growing and Using Stevia: The Sweet Leaf from Garden to Table. Prairie Oak Publishing, 2008
Mowrey, Daniel. Life with Stevia: How Sweet It Is! Daniel B. Mowry, 1992
Kallio, Sandra How Sweet It Is: Sugar Substitute Rebiana OK’d. Wisconsin State Journal, January 9, 2009