Dry organic fertilizer from spent mushroom substrate for sustainable agriculture

Overview

The Microbial Products Lab at the University of Houston–Downtown produces dry organic biocontrol agents and fertilizers from industrial waste streams, including spent mushroom substrates. The current focus is a dry organic fertilizer developed through an energy-efficient process that converts mushroom cultivation byproducts into a shelf-stable, nutrient-rich soil amendment. This approach provides a sustainable alternative to conventional fertilizers derived from animal waste, while addressing the growing challenge of industrial biomass disposal.

The fertilizer delivers key macronutrients such as potassium, phosphorous, and nitrogen, along with essential minerals that promote plant growth. Additional benefits include the potential to increase soil organic carbon and the practical advantage of long-term storability compared to many organic alternatives. The lab is positioned at the intersection of academic research and industrial application, with active collaborations aimed at scaling production and validating performance.

Technical specifications

• Feedstock: Spent mushroom substrate sourced from industrial mushroom production partners, repurposing an existing waste stream
• Product format: Dry organic fertilizer granules suitable for storage, transport, and field application
• Processing approach: Energy- and water-efficient method developed and refined at lab scale
• Nutrient profile: Provides potassium, phosphorous, nitrogen, and minerals to support plant growth
• Soil health benefit: Potential to increase soil organic carbon content
• Storage advantage: Dry format enables extended shelf life compared to many organic fertilizer alternatives
• Co-products: Lab also develops dry algae granules and plant/mushroom extracts as biocontrol agents
• Validation pipeline: Greenhouse plant growth trials conducted in collaboration with Texas A&M University
• Scale-up pathway: Active collaboration with one of the largest mushroom producers in the United States to develop infrastructure for kilogram-scale production

Technology readiness level

The dry organic spent mushroom substrate fertilizer is at an early-to-mid stage of development. The lab-scale production method has been established, and preliminary composition analysis has been completed. The team is currently building infrastructure to produce kilogram quantities for greenhouse trials at Texas A&M University. Planned next steps include optimizing the process for superior growth performance, automating production to reduce processing time and energy/water requirements while ensuring reproducibility, conducting greenhouse and field plant growth validation, and performing a techno-economic analysis to estimate production costs. The process is relatively new, with no published literature available at this time, making it an early-stage opportunity for partners interested in shaping the technology's development and commercialization pathway.