How to Grow Stevia from Seeds
Stevia is a nutrient-rich herb and calorie-free sweetener. Stevia rebaudiana, known as sugar plant, is a shrub native to Paraguay, where it has been used for more than 1,500 years by the local peoples as a sweetener, digestive aid, and topical healing agent.
It was introduced to the rest of the world in the late 19th century and has been used extensively in Asian cuisine for several generations, but has only recently come into widespread use in the United States. This nutrient-rich herb offers protein, calcium, and numerous vitamins and minerals, but its biggest draw is as an all-natural, calorie-free sweetener.
Choosing to Grow Stevia
Stevia is a great alternative to processed sugar. Just drop a leaf into hot beverages or cooked dishes, grind the leaves into powder, or extract the oil. It's heat-stable to 392°F and is 20 to 30 times sweeter than sugar cane, yet it has no calories, does not promote tooth decay, and will not elevate blood sugar levels. This makes it the ideal choice for diabetics and those on weight-loss regimes.
When to Start Stevia Seeds
At just a foot high and slightly wider, stevia can be grown as a houseplant as well as a garden plant, so you can begin the seeds anytime for houseplant use. To grow stevia in the garden, begin the seeds indoors in late winter or direct-sow them in mid to late spring.
How to Start Stevia Seeds
Stevia is best sown indoors in the Bio Dome or seed tray. Drop a single seed in each cell of the Bio Dome or place the seeds on top of the starting medium, and keep them at a temperature of 68 to 70°F. (If your house is colder than this, a heat mat is recommended.)
Outdoors, sow the seeds when the soil warms to 65°F in spring. Germination occurs in 10 to 15 days.
Transplanting Stevia Seedlings
When the seedlings have at least two true leaves, they are ready to be transplanted into the garden. Harden them off for a few days and then transplant when all danger of frost has passed, spacing the plants 18 inches apart in full sun and sandy or light, well-drained soil.
Special Considerations
Stevia likes to stay evenly moist, not too dry and not too wet. Make sure the soil drainage is excellent.
The FDA has declared that the sweetening agent rebaudioside in stevia is safe, but consult a physician before using natural stevia when pregnant or under a doctor's care.
The branches of this plant are quite brittle, so site stevia in an area protected from foot traffic to avoid breakage. Indoors, set it away from the flow of activity in the room.
Growing Tips for Stevia Plants
- During the first 2 months of the growing season, pinch the tips of the plant every 3 weeks. This will result in a bushier, better-branched plant. If possible, pinch in the early morning.
- After planting, do not dig up and move stevia.
- Mulch stevia well, to protect its shallow root system from the heat of the sun.
- Fertilize with a regular (non-lawn) plant food throughout the growing process.
- Pinch off individual leaves as you need them throughout the growing season.
- As soon as the flower buds appear, harvest the entire plant by cutting it at the base and hanging it upside-down in a warm, dry, drafty area for a few days. Do not pinch off the buds or try to postpone flowering; if you do, the leaves will lose their sweet flavor.
- Harvest in the morning, when the plant's sugar content is highest.
Pests and Problems to Watch For
- Bottom-water the seedlings (the Bio Dome is ideal for this) to avoid damping off.
- In the garden, use a soaker hose rather than an overhead watering system if at all possible. Dirt and other debris splashed on the leaves will affect their flavor, so take care when watering, and keep plants spaced a reasonable distance apart.