I have a stevia plant indoors that I've managed to keep alive for three years. It is my only stevia that has survived. I bought it as a small plant at a hardware store. None of the seeds I've purchased have ever sprouted. The plant gets longer and thinner each year. Now it is like a vine, with four stems that are thinner than angel hair pasta. The leaves are sparse and no closer together than about six inches. I have trimmed the plant back and harvested a few dozen usable leaves from it during the past three years. Is that how stevia grows? I thought it would be bushier like basil. It started out that way. I haven't ever used fertilizer, but I raise composting worms in bins and have re-potted the stevia plant and added more rich soil a few times in the past 3 years. Is there something I can do, or something I can add to the soil to make it happier? I want to get more leaves and maybe grow more plants.
Certified GKH Gardening Expert
Your stevia is most likely not receiving enough light. Plants typically become thin and spindly and produce few leaves when they are grown under low light conditions. Increasing the amount of light the plant can access will improve its health and allow you to harvest more leaves.
Place the stevia plant in your sunniest window, and consider purchasing a grow light. If possible, place the plant outdoors during the summer and bring it indoors only during the winter. Please see the following article for more information:
Stevia can be grown from cuttings, which will allow you to produce more plants. Use the same procedure as for basil: