Well, the secret is out, America.  For years, other countries have been using zero-calorie natural sweeteners from the herb Stevia rebaudiana. Stevia is a native of South America, and is widely used on that continent and in Asia.  Japan is the world’s biggest consumer of stevia, and herbal sweeteners made from stevia have been widely available there since the 1970′s.
 

Stevia rebaudinia, a naturally sweet herb, is poised to go mainstream as a sweetener in the United States.  It is an easy herb to grow in your garden.

I was first introduced to the plant twelve or so years ago, when I was studying agronomy at the University of Georgia.  One of my fellow lab techs in the soybean genetics laboratory (a horticulturist by education) brought me a few seeds from his garden and explained what they were. I was surprised that I had never heard of this miracle herb and at that time, stevia was available only in the U.S. in natural food stores.  The ground, dried leaves of the plant are said to be 15 times sweeter than sugar. Extracts are available that claim to be 200-300 times sweeter than sugar, and if you’ve ever tried them, you’ll be inclined to believe that claim.

These days, apparently, the herbal sweetener is going mainstream. I was thrilled two years ago to discover stevia plants in the garden center at my local Wal-Mart, and soon I found them in other garden shops as well. Now stevia is appearing on grocery store shelves. Truvia, my personal favorite store-bought zero-calorie sweetener, is made with rebiana, a stevia extract, and erythritol, a sugar alcohol found in fruits.

Truvia, a zero-calorie sweetener, is widely available grocery stores

Stevia is available from a number of seed companies, but growing it from seed requires a little extra TLC. I have discovered that the seeds need a significant amount of light to germinate. I start the seeds in peat pots, laying the seeds on top of the media and tamping them down a tad to reduce the chance of washing away the seed when I water. I place the peat pots on a shelf in a well-lit window and keep them moist.  Keeping them well-lit and watering regularly with a spray bottle, I have had germination rates upwards of 90% with year-old seeds. Most people get a much lower germination rate. If I don’t plant the seeds extremely shallowly or place them in bright, direct sunlight, I get a much more common 60-75% germination rate with new seeds.

With care, stevia can be grown from seed.  This seed packet is from Johnny’s Selected Seeds.

According to my research, some plants grown from seed may not be as rich as possible in steviosides, the chemicals that make the plant so sweet. I have not noticed that problem with the plants I have grown from seed. However, if you prefer, you can obtain stevia plants in the spring from the garden centers of many big-box stores.

Whether you grow you stevia from seeds or obtain seedlings from your local garden center, set them out after all danger of frost. Many sources recommend planting stevia in full sun, but stevia is also somewhat shade tolerant. Because of the scorching heat in July and August here in Wetumpka, Alabama (zone 8), I prefer to locate my plants where they will be in the partial shade of larger garden plants. This summer in my garden, the stevia plants placed in part shade are doing better than the ones in full sun. Stevia does well as a container plant, too.

According to Johnny’s Selected Seeds, my latest source for stevia seeds, stevia is a tender perennial that is winter hardy in zones 9-11, but it cannot survive temperatures under 45 degrees Fahrenheit. However, in my garden here in the northern part of zone 8, where we have frost regularly and at least one hard freeze each year, they overwinter quite well. To help the plants weather the cold, I cut the bottom out of a clear plastic water or soda bottle, take off the lid for ventilation, and place it over the stevia plant to make a small greenhouse that will protect the plants through the winter. We had quite a cold spell this past winter, and the plants that weren’t covered seemed to perish — but they surprised me in the spring by coming back from the roots. I’ve also noticed that, once the seedlings are established, they are also fairly drought-tolerant. Stevia is a tough little plant!

Set your stevia plants out in the spring in full sun or part shade. They make wonderful container plants, too!

My stevia plants thrive fairly well with little care. I have yet to see one with a disease.  The only natural predators stevia seems to have in my garden are slugs and snails. I use a pet-and wildlife-safe, environmentally-friendly granular slug and snail product in my garden, and the stevia plants grow in peace. You can also catch slugs and some snails by placing a saucer of beer out in the evening. Overnight, slugs will show up for the party, and in the morning, you can retrieve the saucer and dispose of the flat beer and the inebriated slugs.

As with other herbs, harvest stevia regularly to encourage growth, and fertilize as necessary. I place my harvested stevia leaves and plant stems in a colander in a dry, sunny windowsill to dry. When I accumulate quite a few, I process them by grinding them to a powder and placing the ground plant material in a well-sealed jar.

I prefer to grind stevia to a powder because this maximizes the amount of steviosides (sweet chemicals) that will be released with the ground plant material is used. As you can see from the photo below, I have tried several plant-grinding methods for grinding stevia. My favorite is a cast-iron rolling grinder, seen in the bottom left of the photo above. A coffee grinder can be used, but I find that a coffee grinder does not grind everything evenly, and some of the powdered material poofs out into the room during grinding and is wasted.  If you use a coffee grinder, make sure to clean it out well first so that you will not get coffee flavor in your sweetener. I find that ground stevia leaves are very stable and do not seem to lose their sweetness over time.

For best results if using dried leaves and stems for sweetening, grind stevia to a powder. Pictured here are the dried leaves and several tools for grinding them.  Any one of these tools will accomplish the job, but my best tool for thorough, fast grinding is the cast iron rolling herb grinder, bottom right.

You can also make an extract of stevia by boiling it in water or by soaking it in high-test alcohol like vodka. Extracts can be boiled down to a potent syrup.

Used alone, stevia does not crystallize like sugar, so many people prefer to use sugar or a mix of stevia and sugar for baking and other uses that require crystallization. For most dishes though, even sweet tea, stevia is more than adequate as a sweetener once you experiment a little and get the hang of it.

If you use stevia, or have any stevia recipes you like, feel free to share in the comment form below!

In addition, I’ve done a more detailed piece on tools for grinding home-grown herbs entitled “Tools for Grinding Your Home-Grown Herbs.” Here is the link: http://www.naomiwalking.com/?p=685. 

God bless –

Naomi Walking

For more from Naomi Walking, check out Naomi’s website http://naomiwalking.com, or follow Naomi on twitter @naomiwalking.