Stevia, (Stevia ribaudiana), also known as sweet leaf, is a flowering plant in the Aster family (Asteria), grown for its sweet-tasting leaves. The plant is native to Paraguay, where it has a long history of use by the Guarani people. The leaves contain a variety of sweet-tasting chemicals, known as steviol glycosides, which can be used to sweeten or dry sweetened beverages or desserts or to be processed commercially into powdered nonchloric sweeteners. Steviol glycosides, especially the chemicals stevioside and ribiodicide A, can be up to 300 times sweeter than table sugar and are nonglycemic (ie, they do not affect blood sugar levels). Known as a healthy alternative to sugar, the popularity of stevia sweeteners grew worldwide in the early 21st century.
How to Sow
Stevia seeds can be sown quickly indoors and transplanted outside after frost, or sown directly in the garden, or planted as a planted plant.
Sowing Stevia Seed Indoors:
- Stevia seeds are sown 8–10 weeks before the last frost in spring.
- Sow the seeds in an inch deep seed-formula Usually double or triple the amount of seed for other plants as the germination rate may be lower than other seed varieties.
- Sprouts come out in 14-21 days.
- As soon as the sprouts come out, provide plenty of light on a sunny window or grow 3-4 inches under fluorescent plant lights, closing for 16 hours per day, 8 hours at night. Increase light as plants grow taller. Incandescent bulbs will not work for this process as they will become very hot. Most plants require a dark period to grow, not leaving lights on for 24 hours.
- Seedling does not require much fertilizer, according to the manufacturer’s instructions, when they become 3-4 weeks old, using a starter solution (half the strength of a full indoor houseplant meal).
- When soil surface is dry, do not consume water.
- If you are growing in small cells, you may need to transplant the seedlings into 3 or 4-inch pots when the transplanting garden has at least 3 pairs of leaves before transplanting so that they have strong roots to grow. Have enough space for.
- Before planting in the garden, stevia seedling plants need to be “hardened off”. Move the young plants to a sheltered location outside for a week under outdoor conditions. Be sure to protect them from wind and strong sunlight first. If there is a risk of frost at night, cover or cover the containers, then take them out again in the morning. This tight closure process makes plant cell structure difficult and reduces transplant shock and scaling.
Planting Stevia in the Garden:
- Select a location in full sun with average soil.
- Prepare the bed by turning the soil to a depth of 8 inches. Level with a rake to remove clumps of grass and stones.
- Dig a hole for each plant that can rapidly accommodate the root ball. Space plant 18 inches apart.
- Carefully remove the plant from its pot and gently loosen the root ball with your hands to encourage good root growth.
- Also place the top of the root ball with the level of surrounding soil. Fill with soil on top of the root ball. Press the soil firmly with your hand.
- Use the plant tag as a location mark.
- To conserve water and reduce weeds, apply a light wet layer (1-2 inches) above the soil.
How to Grow
- Keep weeds under control during stevia growing season. Weeds compete with plants for water, space, and nutrients, so either control them often by cultivating them or use a mulch to keep your seeds from germinating.
- Multani also helps in maintaining soil moisture and soil temperature. For herbs, an organic mulch of aged bark or chopped leaves gives the bed a natural look and will improve the soil as it breaks in time. Always keep mulch from the stem of a plant to prevent potential rot.
- Water the plants well during the growing season, especially during dry spells, but take care not to over-water. Plants require about 1 inch of rain per week during the growing season. Use a rain gauge to see if you need to add water. It is best to water with a drip or trickle system that delivers water under low pressure at the soil level. If you drink water from an overhead sprinkler, water it early in the day so that it is time to dry before dusk in the evening to reduce disease problems. Keep the soil moist but not saturated.
- Monitor for pests and diseases. Check with your local Cooperative Extension Service for recommended pest control for your area.
- About 40 days after transplanting, the stevia crop is ready. This is best done just before the flower form.
- Stevia leaves are more sweet than stems so only leaves are usually used. They can be used anew for flavor drinks or can be used as a garnish.
- To make stevia powder, dry the leaves. To dry, cut the entire stems in a sunny morning. Tie the stem in small bunches and hang it in a dry, ventilated place out of the sun. Tie the leaves with a stalk. Or, spread a cheesecloth or a window on a screen in a dry or shady spot. Or, leave the dry herbs in an oven for 2-3 hours on a cookie sheet over the lowest heat, leaving the oven door open. Or, use a dehydrate following the manufacturer’s instructions. Crush well before storage. Store in a tightly sealed container in a cupboard, such as a dark, dry place.
Common Pests and Problems
Stevia Common Disease Problems
Alternaria Leaf Spots: On the upper surface of the leaves and with midrib are small, round reddish brown spots with white to gray centers. Wounds may surround the stems and cause wilt. The disease worsens in hot, wet or very humid climates. Burpee recommendation: Avoid getting water on the leaf. Remove infected plant parts and do not work around wet plants. Make full circulation of air. Contact your cooperative extension service for fungicide recommendations.
Botrytis: This fungus causes a gray mold on the flowers, leaves, stems and buds. It thrives in cold wet weather conditions. Recommendation of Burpee: Remove the parts of the affected plants, avoid watering at night and do not water the plant while watering. Ensure that plants have good air circulation. Contact your cooperative extension service for fungicide recommendations.
Damping Off: This is one of the most common problems when starting a plant from seed. The sprout emerges and appears healthy; Then it suddenly becomes apparent and dies without any apparent reason. Soaking is caused by a fungus that is active when there is abundant moisture and the soil and air temperatures are above 68 degrees F. Usually, this indicates that the soil is very wet or contains high amounts of nitrogen fertilizer. Recommendation of Burpee: Keep seedling moist, but do not put in water; Avoid over-fertilization on your seedling; Thin shoots to avoid overcrowding; Ensure that plants are getting good air circulation; If planting in containers, wash them thoroughly in soapy water and rinse in a ten percent bleach solution after use.
Root Rots: Many pathogens cause root roots as well as mature roots. Burpee is recommended: practice crop rotation and do not plant related crops in the same area for many years. Pull and release infected plants. Make sure your soil has excellent drainage. Contact your cooperative extension service for recommendations.
Septoria Leaf Spot: The disease is most severe during the rainy season in closely planted gardens. It usually appears when plants begin to bear fruit. Circular spots with brown centers and black margins are seen on the lower older leaves. Spores of fungi are produced and deepen the center of the spots. There is a progressive loss of foliage and the fruits suffer from sunscreen. Burpee recommends: remove and destroy infected plant debris. Do not handle or brush against plants when wet. Remove weeds that grow nearby.
Stevia Common Pest and Cultural Problems
Stevia’s sweet leaves act as a repellent for most insects. Plants growing indoors have more problems.
Aphids: Sucking insects of green, red, black or peach color can spread the disease as feed on the underside of the leaves. They leave a sticky residue on the leaf which attracts ants. Burpee recommendation: You can also wash them with a strong spray, or use a pesticide soap.
Slugs: These insects leave large holes in the leaf or consume the leaves completely. They leave a mud trail, feed at night and are a problem mostly in moist weather. Burpee recommendation: Raise hands, at night if possible. You can try to attract traps using either corn or beer. For the beer trap, dig a hole in the ground and place a large cup or bowl in the hole; Use items that have steep arms so that the slugs cannot crawl back when they are finished. Fill the bowl about the way filled with beer, and let it sit overnight. In the morning, the bowl should be filled with submerged slums that can be thrown out for birds to eat. For a cornmeal trap, put a tablespoon or two of cornmeal in a jar and place it on the side near the plants. The crooks are attracted to the smell but they do not digest it and it will kill them. You can also try to place a barrier around your plants of diatomaceous earth or even coffee grounds. They cannot crawl over them.
Thrips: Thrips are small needle-thin insects that are black or straw colored. They suck the sap of plants and attack flower petals, leaves and stems. The plant will have a stippling, disordered falking or silverying of the leaf surface. Thrips can spread many diseases from plant to plant. Burpee Recommendation: Many thrips can be replaced with sheets of aluminum foil spread between rows of plants. Remove the weed from the bed and after the frost remove the debris from the bed. Check with your Cooperative Extension Service for pest control.
Whitefly: These are small white flying insects that often arise in the cloud when plants are disturbed or brushed against them. Burpee recommendation: They are difficult to control without chemicals. Try hot pepper wax or pesticide soap. Check with your Cooperative Extension Service for pesticide recommendations.
Is stevia challenging to grow from seed? Yes, stevia can be challenging to grow from seed. This is because it has a low germination rate and it sprouts slowly. It is very easy to grow from transplanted plants.
Can I leave stevia in my garden in winter? Stevia is a tropical plant and cannot survive cold temperatures. It will survive for a few years in areas with warm winters.
Can I bring my stevia in for the winter? You can bring it in and grow it in a sunny place. When the plant has grown, we would recommend cutting it back when you bring it to rejuvenate.
Are flowers edible? Stevia is grown for its sweet leaves instead of flowers, and the leaves must be harvested before flowering for the best sweetness. If you allow the plant to flower, you can save the seeds for reuse, or use them as cut flowers.
Stevia is related to sugarcane? No, stevia is a South American native that is related to sunflowers and asters. It does not contain sugar, but its crushed leaves have a sweeter taste than sugar without calories.