After all the theoretical stuff around stevia on this page, we thought growing our own stevia and reporting about it would be a nice variety. We will do a detailed report on our experiment, and if it will be successful, other “experiments” like testing different recipes, creating an extract or multiplicating the plants will follow.
Last Saturday we started the experiment. We wanted to see if it is really that hard to grow the seeds. According to different sources, the spawn rate of them lies at only 10 to 20% or even less. Many people report that they had not got any results at all, and when they had the luck to get some little plants out of the seeds, it also would have been hard to pull them through. Then when the plants finally are grown up it seems to be easier to keep them alive, if you don’t overwinter them outside. We already wrote an article about growing stevia, when you need some fast tips on it. We will maybe revise this article if we get some new insights in our own experiment.
Here is what we have done, you can use it as a manual to grow your own stevia, but we cannot guarantee that it will work, we are no expert gardeners ;)

First we compounded our own prick out substrate. Therefor we took one half of standard potting soil and another half of sand. We strained the soil through a normal plastic sieve to get it it more fluffy. Then we mixed it up with the sand until we got a homogeneous mass and put it in a oven-safe container. We used an old casserole for it.

After this we put the mix in the oven at 120 °C for about 30 minutes. This is to make sure that there are no other germs or vermins which could disturb proper growing of the stevia seeds. The high temperature will also make the substrate pretty nutrient-poor, which will “motivate” the seeds to develop stronger roots to get the necessary nutrients.

When we took the substrate out of the oven it was very dry, loose and looked much more gray then before, just as if we put 100% sand in the oven, and not half-half. After watering and mixing the substrate again, we received something that rather could be called “earth”. For watering you should use a watersprayer, it’ll make dosage much easier. You should always keep the soil wet, but avoid stagnant moisture.

After this we pressed the mix softly on with the hand, then we strew the stevia seeds on it, and pressed them on the soil again. You have to make sure that the seeds have contact with the soil, and also do not cover the seeds with earth, as the stevia seeds need light to sprout.

After watering the seeds we took some cling foil, put it over the seeds (not completely airtight) and placed the container at a windowsill with much exposure to light. As you can see on the right picture, we had to fix the foil with some clips, and also that after one day water condensed on the inner side of the foil.

The experiment was started last saturday (02/12). We don’t really know how often we should water the seeds, so I checked the moisture everyday. The first time I watered them again was after 4 days. We also ventilated the container for one hour. The instruction which came with the seeds says that you should do this every three days. Now it’s one week after we started the experiment. We are hoping to see some results in another one or two. When the first seeds begin to sprout, we’ll update.
Please wish us luck ;)
PS: If you got any expert tips for us or just something to say or ask, let us know in the comment section of this post.