Here are the requirements for growing stevia from seed:
- Seed soaking: Stevia seeds do not require soaking before planting.
- Germination requirements: Stevia seeds require light to germinate, so do not cover them deeply with soil.
- Seed planting depth: Plant stevia seeds 0-1/8 inch deep in well-draining soil.
- Temperature range for germination: Stevia seeds germinate best at temperatures between 70-75°F (21-24°C).
- Days until germination: Stevia seeds typically germinate within 7-14 days.
- Indoor vs outdoor planting: Stevia can be started indoors 8-10 weeks before the last frost date or sown directly outside after the danger of frost has passed.
- USDA hardiness zone and frost hardiness: Stevia is hardy in USDA zones 9-11 and can be damaged by frost.
- Annual vs perennial: Stevia is a perennial herb in warmer climates and an annual in colder climates.
- Seed spacing and thinning: Plant stevia seeds about 18-24 inches apart and thin to one plant per pot or 24-36 inches apart in the garden.
- Plant spacing: Space stevia plants 24-36 inches apart in the garden.
- Sunlight requirements: Stevia requires full sun to partial shade and 6-8 hours of direct sunlight per day.
- Height range for mature plants: Stevia can grow up to 3 feet tall.
- Transplanting: Transplant stevia seedlings outside after the danger of frost has passed and the soil has warmed up.
- Flowering: Stevia produces small, white flowers in late summer or early fall, but it is primarily grown for its sweet leaves.