Controversy has surrounded Superthrive for many, many years, but to us, just the idea that it has survived all the negative press must mean there's something beneficial in it. We have testimonials and recommendations from the Golden State Bonsai Federation, Bonsai Clubs International, the Greater New Orleans Bonsai Society, the California Bonsai Society, the American Bonsai Society, and many others. It is a mixture of vitamins and minerals that, to us, greatly enhances the production of roots especially in a newly repotted bonsai. We put a few drops in several gallons of water for our trees to soak in for about 20 minutes when we have them repotted, and the Superthrive helps them become acclimated to their new soil by encouraging new root growth. We recommend it for any of your bonsai, indoor and outdoor, conifers, evergreens, and deciduous. This is an 8 oz. bottle.