The Amazing New Way to Grow Tomatoes: In Tomato Waste.

The Amazing New Way to Grow Tomatoes: In Tomato Waste. Closed-loop systems, in which waste is used as a nutrient (usually) could well be one of the futures of farming: The goals of minimizing waste and optimizing energy use are rubrics that are becoming increasingly essential. But here's one we haven't heard of before, at least not in quite this way: turning tomato waste into a medium for growing tomatoes. A new study out of New Zealand and published in the journal HartScience, comes up with a way to reuse green waste in a hydroponic system—and even better, that waste can come from the crop itself. There are two main concepts to understand here before you can grasp exactly why this is such an interesting idea. The first is biochar, which is basically charcoal created from “green waste,” which is exactly what you think it is. Charcoal is created through heat in an environment without oxygen; often that’s done by burying. The biochar in this study comes from the waste of tomato plants (stems, roots, leaves). The other concept is the substrate. In a hydroponic system, when a plant is planted in what’s basically a moving stream of water in which nutrients are dissolved, the substrate is a porous bit of…something…that holds the plants in place. Most commonly the substrate is spun rock (a.k.a. rock wool), which is basically cotton candy made of rock. Sawdust is also a pretty popular substrate. more