Stevia rebaudiana

stevia-05Stevia, also known as the Sugar Plant, has leaves that are very sweet yet calorie-free.  The active compounds responsible for the sweetness are the steviol glycosides (mainly stevioside and rebaudioside).

Apr 7, 2016 = Day 0.  Plant started from seed (Park Seed Co.).  Seeds sowed in 1.5-inch rockwool cube in 2-inch net-pot.  Moistened with dilute fertilizer solution: 1.2 mL (1/4 tsp) Dyna-Gro Liquid Grow, 0.8 mL pH Down per gallon of tap water. N-P-K (in ppm): 22-12-13.  pH = 6.0.

Apr 11 = Day 4.  Plant germinated, placed directly under a fluorescent light (2 ft. T8 bulb, 17W, 6500k) for 16 hours per day.

IMG_20160419_162324588 (1)
Apr 19 = Day 12

Apr 22 = Day 15.  Installed plant into 3.5-gallon bucket.  Hydroponic solution composed of 3.5 gal (13.2 L) tap water, 7 g MasterBlend 4-18-38, 7 g calcium nitrate, 3.5 g magnesium sulfate, 0.7 mL Dyna-Gro Pro-TeKt, 3.5 mL pH Down. N-P-K (in ppm): 103-41-168.  pH = 6.0.  Plant moved to indoor grow room, receiving 8 hours LED grow light per day, plus 3 hours sunlight per day.

IMG_20160502_110945019 (1)
May 2 = Day 25
IMG_20160526_142306558 (1)
May 26 = Day 49
IMG_20160616_122418126 (1)
Jun 16 = Day 70
IMG_20160706_125841009 (1)
Jul 6 = Day 90

Jul 13 = Day 97.  Entire plant was harvested, cut at the base.  Total fluid used = 1.5 gallons.  Final pH = 5.0.

IMG_20160713_102227605 (1)
Jul 13 = Day 97.  Root system of Stevia plant.

To dry the leaves, plant was hung upside-down in a well-ventilated room.  After a week, the dried plant leaves were crumbled and stored in an airtight container.

To extract the steviol glycosides from the dried leaves, I followed the following procedure:

Put the dried, crumbled stevia leaves into a glass container.
Add 1 cup vodka (I used SKYY vodka).  Cover and let it sit for 36 hours.
After 36 hours, filter out the leaves using a funnel and a coffee filter.
Using a low heat setting, evaporate off the alcohol with constant stirring (takes about 20-30 minutes).  Don’t let it come to a boil, or it will burn the extract.
Store the finished sweet extract in an airtight container in the fridge.