The economic significance of mushroom cultivation cannot be overstated, contributing to revenue generation and
possessing notable nutritional and medicinal attributes. However, global production has been suboptimal,
registering only 3,414,392 tons in 2007 with an annual growth rate of 5.6%. Particularly, mushroom production in
Africa remains minimal, with Kenya demonstrating a lackluster performance, producing a mere 500 tons annually
and relying on imports (150 tons) to meet domestic demand. This low output in a country rich in agricultural
waste resources raises concerns. The study addresses the inadequately researched aspects of mushroom
cultivation, focusing on critical factors such as growing houses, substrates, pests, temperatures, and relative
humidity. The central research question probes the impact of growing condition management on the performance
of smallholder mushroom farmers. The study draws on the Resource-Based Theory and employs a conceptual
framework to guide the research. Employing a descriptive research design, the study encompasses a population of
300, with a sample size of 30 respondents selected through simple random sampling. Questionnaires were
administered for data collection, and the analysis was conducted using the Statistics Package for Social Science
(SPSS version 12). Key findings include the revelation that 90% of mushroom growers possess adequately
ventilated growing houses, but none have a thermometer or radiometer. Additionally, 43.3% of growers utilize a
mix of substrates, while 93.3% are aware of the prevalence of pests and diseases. The study concludes that effective
management of mushroom growing conditions significantly impacts the performance of oyster mushrooms. In
light of these findings, the study recommends further research on mushrooms, an increase in agricultural
extension services, and the establishment of a Mushroom Training Institute. The insights derived from this
research are anticipated to benefit policymakers, academicians, scholars, and mushroom growers alike.