One plant we hear about more lately is Stevia. Stevia ribaudiana is a native to Portugal, and possibly other areas, as that was one of my sources some years ago.
Stevia is many times sweeter than sugar, and can be substituted for sugar in many recipes. The main use I have for it is to sprinkle a few bits of the dried leaves in my herbal teas.
What I find so interesting about it that has always been extremely difficult to grow for more than a few generations. It produces beautiful tiny white flowers, very similar to that of tomato, but upon replanting the dried seeds from the flowers, I rarely achieved greater than 15-20% germination.
Last year I placed a new, small potted Stevia plant on the soil in one of our larger fig trees, hiding it hopefully from our occasionally free-roaming goats. The goats did not destroy it and it survived the winter indoors with the fig tree. Imagine my surprise when I noticed several volunteer Stevia plants growing in the soil of the fig tree--in the soil directly under the Stevia plant. The funny thing about this is maybe I have been trying too hard! The Stevia germinated and grew on its own with no help of mine.
OK, that's my little story on growing one's own sweetener, and avoiding using white sugar which is a product usually of high-pesticide abused sugar plantations. Save the planet and grow your own sweetener.
Enjoy the pictures.
Linda