Toward nutrient cycling from organic waste streams for soilless cultivation

Soilless cultivation offers multiple benefits, such as higher productivity, reduced pesticide use, maximised water use efficiency, and protection from adverse environmental conditions, and will play an ever-greater role in providing food for the growing population. Whilst hydroponics denotes the use of nutrients of mineral origin, bioponics connects organic waste streams with microbial transformation and soilless cultivation, placing it at the centre of circular food production. Commercial bioponic growers need industrially produced fertilisers that are consistent in their quality and produce comparable yields to mineral fertilisers. This opinion piece examines four key issues that we think will determine whether recovered fertilisers become widely adopted by commercial soilless growers — efficacy, safety, sustainability, and economic viability — and concludes by proposing a roadmap to guide their development.