Native to subtropical regions Stevia is a plant species considered a natural sweetener. They have zero calories are 40 times sweeter than sugarcane. Common to ancient Brazil and Paraguay it is used in herbal tea/medicine. The plant has elliptic leaves, grow 90cm height have zero calories.
Although there are many types only 6 are used as natural sweeteners. Common types include Stevia Eupatoria, Stevia Rebaundiana, and Stevia Plummerae. Others are Stevia Salicifolla, stevia Ovata and Stevia Serravia.
- Stevia Eupatoria
- Stevia Rebaundiana
- Stevia Plummerae
- Stevia Salicifolla
- Stevia Ovata
- Stevia Serravia
Commercial properties are natural sweetener, low calorie, high glycosides, non-fermentable. Others are long shelf life, natural anti-microbial properties, and no-coloring. The major attraction is the natural product, high natural elements, non-toxic, no-negative health effect reported.
The plant is highly adaptable to different climatic conditions easily propagated. Grow them from seed or part of plant, allows intercropping. A farmer harvests up to 3 to 4 times a year because they take average of 4 months.
- natural sweetener
- low calorie
- high glycosides
- long shelf life
- natural anti-microbial properties
- high natural elements
- no-negative health effect
- highly adaptable
- easy to grow
- fast harvest
Uses of Stevia
Commercial Stevia cultivation involves organic farming, transportation, and cost of production. Other cost considerations are labor, transportation. The plant is used as a natural sweetener, weight loss, anti-inflammatory or antibacterial plant.
- natural sweetener
- weight loss
- antibacterial plant
Farmers face a few challenges in cultivating the plant. First the initial growth rate is slow, herb highly sensitive, low resistant to drought. More include slow seed germination, low tolerance to high PH levels weed cropping affects plant, sensitive to waterlogging, frost.
- Slow initial growth rate
- highly sensitive
- low resistant to drought
- slow seed germination
- low tolerance to high PH levels
- weed cropping affects plant
- sensitive to waterlogging or frost
Investment details involves supervision, irrigation manual weeding. Others are leaves processing, sowing of seedlings, manure, and land preparation.
Advantages of stevia cultivation
There are many advantages to cultivating stevia. They improve cardiovascular health are nontoxic, no artificial agents. Others are control of obesity, blood pressure, and yeast infection. More include having defensive microbes, high natural sweetener, no-calories, improves gastrointestinal activity.
- improve cardiovascular health
- no artificial agents
- control of obesity
- blood pressure
- yeast infection
- defensive microbes
- high natural sweetener
- improves gastrointestinal activity
Best cultivation climate is subtropical therefore grow them in good light in semi-humid temperature. Plant in well drained sandy loam soil with PH level 6 to 7.
Provide good organic matter in soil, irrigation and raised bed of 15cm. Space them 20-25cm spacing or 50cm. Land preparation involves planting them in 1 hectare at a rate of 100,000 to 1m plants.
There are 2 ways to grow stevia propagation or seed. Propagation is very effective because they easily root with this method. Select plant with 3 nodes for propagation for better survival rate.
The best time to plant seeds in soil is rainy season. Use phosphorous 30kg.ha, potassium 45kg/ha, nitrogen 60kg/ha. Irrigate 3 times daily remove weeds at regular intervals. Use raised beds apply mulching to reduce weed growth.
Disease and Pests
Common pests are caterpillars and cutworms. Diseases include root rot, septoria, leaf spot, and leaf blight.
The plant is harvested at 4 months by pinching and remove 5cm of branch. Dry the leaves in sun or use artificial methods at 50c for 6 hours. Leaf moisture is sustained at 4 percent while threshing is done to remove stem and leaves. Post-harvest involves extracting the sweeter compounds from the dry leaves.
Processing and extraction
Leaves are dried then threshing is applied to remove leaf from stem. Leaves are laced in cool dry area in airtight container. Extraction process is highly technical and involves purification and processing methods. Solvent extraction goes through filtration, crystallization and precipitation. Commercial producers require certification from regulatory food and drug authority.