Biological crop inputs and regenerative agriculture practices are increasingly used to support plant health by influencing soil microbial communities and processes. Yet their effects are hard to verify in real time on farms. Growers often apply a biological product without a practical way to confirm it is active in soil, persisting as intended, or delivering measurable impact, making it hard to optimize application timing, dosage, or management practices. 

In principle, soil biology can be assessed with laboratory assays (e.g., microbial profiling, metabolite testing), but these methods are not feasible at scale for smallholder systems. Sending samples to centralized labs adds cost, delays, and logistical burden, and often requires manual preparation and repeat field visits. In practice, many in-field probes rely on electrical conductivity or ion proxies, but these signals are influenced by dissolved salts (e.g., from soluble fertilizers and irrigation water) and require site-specific calibration, making them poor indicators of microbial activity. 

A practical, automated, in-soil sensing approach is needed to provide interpretable indicators of biological activity or “microbial fingerprints”, such as volatile organic compounds (VOCs), spectral signatures, or other validated proxies. Such technology could enable monitoring across large grower networks and diverse soils, support in-season decisions, and increase confidence that biological and regenerative interventions are functioning as intended.