Stevia rebaudiana, commonly known as Stevia, is a plant native to South America, used for centuries as a natural sweetener. The intense sweetness comes from steviol glycosides in the leaves, which the human body does not metabolize for calories. Growing this herb at home provides a pure, zero-calorie sugar substitute, bypassing highly processed commercial products.
Cultivating Stevia for Maximum Yield
Stevia is a tender perennial that thrives in warm climates but is typically grown as an annual in temperate regions because it is not frost-hardy. For maximum productivity, choose a location that receives full sun (at least six to eight hours of direct sunlight daily). Intense light encourages the production of sweet glycosides within the leaves.
The plant requires loose, loamy, and well-draining soil to prevent root rot. If planting in the ground, space young plants about 18 inches apart to allow them room to mature. Growing Stevia in containers is beneficial for gardeners in cooler zones, as the plant can be moved indoors before the first frost.
Stevia needs consistent moisture to support its rapid growth, but it cannot tolerate soggy conditions. Frequent, light watering is preferable to deep, infrequent soaking, especially during the peak summer months. To encourage a dense, bushy structure, regular pruning of the growing tips during the vegetative stage is highly recommended. This practice, known as pinching, promotes lateral branching, which significantly increases the total leaf harvest.
Best Practices for Harvesting Stevia Leaves
Timing the harvest is important to maximize the concentration of steviol glycosides and ensure the sweetest flavor. Leaves reach peak sweetness just before the plant begins to flower, typically in late summer or early autumn as day lengths shorten. Once small, white flowers appear, the plant redirects energy away from leaf production, and the flavor becomes less appealing.
To maintain maximum sweetness, pinch off any developing flower buds immediately. For the main harvest, cut the entire plant down, leaving a stubble of four to six inches above the soil line. This technique ensures the plant remains vigorous for a potential second flush of growth before cold weather arrives.
Harvest the leaves in the morning after the dew has dried, as the concentration of sweet compounds is often highest then. Use sharp, clean shears to cut the stems cleanly. Focus on collecting leafy stems and discard any woody or damaged portions.
Preparing and Using Stevia Sweetener
The simplest way to use Stevia is by adding fresh leaves directly to beverages. Heat best releases the sweetness, making it an excellent addition to hot tea, where one to four small leaves usually sweeten a single cup. Steep the leaves along with the tea for a few minutes and then remove them.
For longer storage, leaves must be properly dried. After harvesting, strip the leaves from the stems. They can be dried by spreading them in a thin layer on a screen, or by hanging small bundles of stems in a warm, dark, and well-ventilated area. Leaves are fully dry when they become brittle and crumble easily (1–3 days). A food dehydrator set to 100°F can also speed up this process.
Once completely dry, the leaves can be crushed or ground into a fine green powder using a coffee grinder or food processor. Store this powder in an airtight container away from light and moisture to retain sweetness. Note that this green powder does not dissolve perfectly in liquids and retains a stronger, herbal flavor compared to commercial white extracts.
A concentrated liquid extract is popular for long-term storage and cooking versatility. For a water-based extract (which has a shorter shelf life), steep crushed dried leaves in near-boiling water for up to 24 hours before straining and refrigerating. A more potent, shelf-stable extract uses high-proof alcohol, such as vodka.
To make the alcohol extract, loosely pack a jar with fresh or dried leaves and cover them with alcohol. Steep the mixture in a dark place for a maximum of 48 hours; steeping longer pulls out bitter compounds. After straining, gently heat the liquid (without boiling) to evaporate the alcohol, concentrating the sweetener into a thicker syrup.