One thing that often gets glossed over is the quality of the inputs for sprout cultivation—like seed sourcing and water usage. If you’re not careful, you can end up relying on seeds treated with questionable fungicides, or using a lot more water than anticipated. There are some interesting small-scale trials (check the EU’s “Circular Agronomics” project) that use graywater systems for sprout rinsing and compost the spent roots and seed hulls, essentially closing the loop. However, reusing the rinse water takes real attention to microbial safety.
As for residue, most of it is highly compostable and can even be vermicomposted (worms love the fine roots). I’ve seen a couple of urban farms mix sprout waste directly into bokashi bins to accelerate breakdown. But the best practices are very context-dependent—what works in an indoor microgreen setup might not apply to larger sprouting operations. Curious if anyone’s seen a zero-waste workflow that scales without running into pest or mold issues over time?