Stevia Rebaundiana Bertoni - Sweet leaf

Stevia Rebaundiana Bertoni is a useful herb that few gardeners grow. The leaves of the plant are dried and used as a non-chemical, sugar substitute that has zero calories and is safe for diabetics.

A member of the aster plant family, there are 200 varieties of Stevia that are related to lettuce and marigolds. S. Rebaundiana Bertoni is the only variety used as a sweetener.

Some people say fresh Stevia leaves have a licorice flavor. The dried leaves are ten times sweeter than sugar and are added to tea and made into extracts. A concentrated syrup is made from dried leaves and water.

Stevia leaves and stevioside extract tablets and powder are also available. When the sweet quality is harvested from the leaves, one half teaspoon of the extract is 300 times sweeter than refined sugar.

Unfortunately, some producers use stems in the manufacturing process, leaving a bitter taste when the Stevia is used in foods.

White powder Stevia is concentrated stevioside. It is so strong that producers add fillers such as milk lactose or maltodextrin from corn, rice or tapioca to reduce the potency.

Powdered steviosides are dissolved in water, alcohol or glycerin and sold as a clear product. In Japan, stevioside is mixed with fruit and grain based erythritol. The product is calorie free, promotes dental health and is safe for diabetics.

Coca-Cola and Cargill developed their own Stevia based product called Truvia. Pepsi developed Pure Via for its zero calorie beverage market. Dr. Pepper’s zero calorie drinks use Reb A as the nickname for their Stevia extract.

The plants are relatively easy for home gardeners to grow during the summer. The leaves are harvested in the fall, dried for a day, and stored for use.

Dried leaves are added to tea, used as a substitute for part of the sugar in ice cream or fruit desserts or sprinkled on cereal. Stevia cannot be directly substituted in cake or bread recipes since refined sugar is part of the chemistry of those recipes. The website stevia.com provides recipes for many sweets.

The Guarani Indians of the Amambay Mountains in Paraguay grew Stevia for centuries before westerners discovered it. The Guarani grew K’ a’ he'en to sweeten their bitter mate teas, to sweeten medicinal potions and as something sweet to chew. Written records show that Stevia was used in Brazil and Argentina by the 1800s.

Dr. Moises Santiago Bertoni, a Swiss born, (1857) Italian plant explorer and botanist, thought he had discovered the plant when he found it growing in the mountains of Paraguay in 1887. Bertoni named the Stevia Rebaudi in honor of the Paraguayan chemist who was the first to extract the plant's sweetness.

Bertoni moved to Paraguay in 1884 where he and his wife Eugenia Rebaud Bertoni (Married 1876) raised 13 children while conducting research on the Guarani Indians. They self-published their writings through their own publishing company called Ex-Sylvis, which means from the forest. Their house is now a museum.

Stevia was grown commercially after Bertoni wrote about it and by 1908 the first commercial crop produced a ton of dried leaves.

The sweetness of Stevia leaves is said to be unpredictable when the plant is grown from seed. Sources: Burpee Seeds at burpee.com and Johnny’s Seeds at Johnnyseeds.com.

In the spring, the plants will be available from Moonshadow Herb Farm in Muskogee. Mailorder sources include Mountainvalleygrowers.com and Possumcreekherb.com.

Stevia is a tropical plant that thrives in full sun or afternoon shade. Plant them 18 to 24-inches apart when temperatures are at least 60 during the day and the soil warms. The plants’ roots stay close to the soil, so use mulch to keep them evenly moist.