I would like to grow Stevia R as an indoor plant, is it possible? Where would I be able to get the seeds or a small plant in GTA?
Thank you for contacting the Toronto Master Gardeners.
Stevia like basil is considered a tender perennial herb (in USDA zones 9 – 11), in Toronto ( zone 6) it is grown as an annual.When planted outdoors, Stevia prefers full sun, loamy, moist, well draining soil with good air circulation around the plant. During the first 2 months of the growing season, pinch the tips of the plant every 3 weeks. This will result in a bushier plant. Stevia does not like to be moved once its planted, so make sure to pick the ideal location before planting. Mulch Stevia well, to protect its shallow root system from the heat of the sun.
Pinch off individual leaves as you need them, making sure not to remove more than 1/3 of the leaves at one time. 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, 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 flavour.
If you decide to grow Stevia indoors on a windowsill, your success is likely to be only modest, this is because herbs, in general do not like to be grown indoors. They refer to be planted directly in the ground or in pots outdoors. If you do decide to attempt to grow Stevia indoors it will grow satisfactorily under standard fluorescent lamps, and exceptionally well under high output T5 fluorescent plant lights, compact fluorescent, or high intensity discharge (metal halide or high pressure sodium) plant growing lights. Keep standard fluorescent lamps between 2 and 4 inches from the tops of the plants, high output and compact fluorescents approximately one foot above the plants, and HID lights between 2 and 4 feet above the plants, depending on wattage.
When growing from seed it should be noted that germination of Stevia seeds is spotty. Seeds should be sown 8 to 10 weeks before the last frost date, which for the Toronto area is May 9th. Germination is best between 21 to 24 C. Seedlings should emerge in about 7 to 21 days. When seedlings are large enough to handle, you can transplant them into 3-inch diameter pots and keep them inside until nighttime temperatures are above 10 C consistently.
Toronto Master Gardeners do not recommend specific retailers, however I have found Stevia plants in the herb section of most garden centers. If you google “Stevia seeds” you will find numerous suppliers.