20 seeds. Start Stevia seeds and grow this well-known culinary herb that is used as a sweetener. The leaves are 20 to 30 times sweeter than sugar cane, but with no calories or carbohydrates. This makes it not only safe for diabetics but also beneficial. Dieters also benefit from the sweetening of Stevia herb without the harm that artificial sweeteners are known for. The leaves can be applied directly into drinks or made into tea. The dried Stevia leaves can also be ground into powder and used in recipes that call for green Stevia powder. For sweetness, 3 table spoons fresh leaves, or 1 teaspoon powder equals 1 cup of sugar.