Custom Agronomics

David D. Johnston, the firm's President, directly originates and governs all investments. Johnston typically takes board seats at portfolio companies, indicating a centralized decision-making structure with no publicly identified investment committee or outside advisors.

The firm concentrates on early- to growth-stage companies developing biological crop inputs, soil-microbiome products, and specialty nutrient delivery systems. Positions include BioConsortia, Pathway Biologic, Concentric Ag, and Nutri-Tech Solutions — spanning venture-stage microbial discovery to operational manufacturing and distribution scale-ups.

There is no public evidence of the firm investing outside biological and specialty-nutrient technologies for agriculture. The portfolio is intentionally concentrated in companies developing biostimulants, microbial consortia, and micronutrient systems — avoiding farmland, commodity trading, and generalist agtech.

The firm does not publicly describe its origination process, but Johnston's board-level involvement across portfolio companies suggests a network rooted in the biological-agriculture research and manufacturing communities in North America and Australia. The firm does not appear to participate in broader family-office co-investment clubs or syndicates.

Custom Agronomics is structured as a single-family office — it deploys capital as an investor, not a manufacturer of agricultural products. However, Johnston's hands-on governance model and board seats blur the line between passive allocator and active operating principal.