My dearest readers, I come to you as but a humble gardener who, for your delight and whimsy, has traipsed into the wondrous world of science. When I could find no satisfactory information on an intriguing sweet leaf plant, I took it upon myself to test my ideas and curiosities upon the stone of the scientific method.
In this column, I break down the mysteries of stevia: What it is, what it’s for and how to make the most of it. (I hope someone finds this useful, because it took me half a summer of research to figure this schnitzel out.)
Stevia is an annual herb, sometimes called sweet leaf. This member of the aster family has — surprise surprise — incredibly sweet leaves, and it’s known for having a slight licorice or herb aftertaste, depending on how the plant is processed and to what degree it’s being used.
With stevia, less is often more. It’s a popular sweetener because it’s natural, has zero calories and does not cause a rise in blood sugar the way many other natural and artificial sweeteners do. If you’d like to try stevia, be aware that many brands mix it with other sweeteners. Try looking for a liquid variety that clearly says it is pure stevia. My favorite is the SweetLeaf brand.
But let’s get real. We’re not here for shopping advice. We’re gardeners. We want to know if this plant is worth all the fuss. Well, I can tell you, I grew six stevia plants this year, and this herb is incredibly low-maintenance. It’s sun-loving; it’s fairly drought-, pest- and disease-resistant; and it wouldn’t mind getting fertilized once or twice if you’re feeling fancy.
When I harvested my stevia, I made sure to take no more than a third of each plant, cutting just above a set of leaves. I then stripped, washed and processed the leaves just about every way I could think of. I chopped and brewed them, dried them, froze them and even distilled them. I tried all of these methods multiple ways based on the somewhat sparse information I found online. Below are my findings:
- Using stevia fresh works best if you brew it alongside your tea in its own loose-leaf strainer. I didn’t find many other uses for it in this form. I recommend chopping it first and using more than you think you’ll need, since fresh stevia isn’t quite as sweet as dried. This method takes more prep in the moment than I usually prefer, but it’s a fun treat to go out in the garden, pluck a few leaves and brew them into something refreshing.
- Drying stevia is a good, relatively hands-off way to make your stevia last. Once it’s dried, it can be brewed with your tea or coffee, or even powdered and used in baking. I tried this in zucchini bread, and it was quite the success. (But remember that, being an herb, stevia won’t dissolve and will show up as green specks in your baked goods.)
- I tried drying the stevia two ways: in my dehydrator and hanging to dry. To my surprise, the air-dried stevia was sweeter, had almost no bitter aftertaste and retained much more of its color than any of the dehydrated batches. To dry, string the stevia leaves up with floss or lay them on a baking sheet in a sunny spot.
- Freezing herbs is actually a fairly new concept for me, but I’ve fallen hard and fast. When I’m whipping up a fruit-and-greens smoothie and my fruit just isn’t sweet enough, stevia can be pureed right in. Just be careful not to use too much — this stuff is sweet! And, if you’re not feeling the whole healthy-hippie-smoothie thing, I’ve got two words for you: margaritas and mojitos. You can make some amazing mixed drinks with your frozen stevia.
And now, we come to the part where I went full-blown, Brit-Brit-the-Science-Chick on my stevia investigations. Since I prefer to use a liquid stevia in all of my beverages and many of my sauces and desserts, I was super excited about making my own stevia extract.
Since the info online wasn’t complete enough for me, I experimented. I made seven batches of stevia extract with different variables, such as whether I used water or vodka to create the extract, whether I chopped or minced the fresh stevia leaves, how much vodka-to-stevia I used and more.
First, water versus vodka: Both worked quite well. I liked the taste of the water extract better, but since it takes little extract to sweeten something, the flavor difference is minor. Water is obviously the cheaper of the two options, but it has one major downside: it only lasts about two weeks in the fridge, whereas the vodka extracts have lasted a month so far and I’m told may last as long as three months.
If you prefer to use water, you can sidestep this issue by freezing most of your extract and only keeping small amounts thawed for daily use. I found that freezing the extracts had no effect on the flavor or sweetness, so you can make huge batches of extract to last the entire year.
Liquid-to-stevia ratio: I tested this pretty extensively, and I’ve found one cup of loosely packed stevia leaves to half a cup of your liquid of choice does the trick. I also found that mincing your stevia makes a much more potent product, so once you’ve measured, make sure you mince those puppies!
I tested all of my batches against store-bought stevia as well as regular sugar. It took one teaspoon of sugar to get eight ounces of black tea to my desired sweetness and five drops of SweetLeaf brand stevia to do the same. It took 11 drops of my best batch of extract to get to a similar sweetness.
In the batches where I only roughly chopped the leaves or changed the liquid-to-stevia ratio, it took as many as 50 drops to get to a similar sweetness. My extract did have a bit of an herb-like flavor and was not clear the way the distilled, store-bought variety was, but I still consider this an unmitigated success.
If you’d like to try making your own extract, here’s what worked best for me: Measure one cup of loosely packed stevia leaves, then mince them. (I used a food processor.) Put your minced leaves in an airtight jar with half a cup of vodka or water, covering the leaves as much as possible. Then place the jar in a cool, dark place. (I used my fridge.) Leave it there, shaking it occasionally, for 36 to 48 hours, but no longer, or the extract may become bitter.
Separate the liquid out with a coffee filter or similar strainer. In a small saucepan, simmer the liquid on low for 20 to 30 minutes. Avoid boiling the liquid or cooking longer than a half-hour, which will make your extract very bitter.
Strain the liquid one more time and put it into an airtight container. I recommend a dropper bottle, since stevia extract is generally measured in drops. Then refrigerate for up to two weeks for water extract or three months for vodka-based extract. If you make a bunch at once, freeze your extra extract.
And that’s it! We have unraveled the mysteries of the perhaps-not-terribly-mysterious stevia plant. I will definitely be growing more next year, now that I know how to use this fantastic plant.