Despite the continued production and overdependence of traditional crops mainly maize and wheat as main source of income in the Uasin-Gishu County, poverty among farmers has been increasing. To mitigate the poverty effects, farmers have tended to substitute land under the traditional crops for high yielding and high value crops passion fruit inclusive. However, the uptake of passion fruit has been achieved with partial success. This study examined factors affecting passion fruit adoption and the extent of adoption. It further investigated the comparative profitability of passion fruit crop vis-à-vis other farm enterprises contingent on available farm resources. Cross-sectional data from 100 randomly selected farmers were collected and subjected to Heckman two-step regression analysis to determine factors affecting passion fruit adoption as well as the extent of adoption. Gross Margin Analysis and Data Envelopment Analysis methods were used to assess the comparative profitability of passion fruit crop. The results showed that availability of water for irrigation, title deeds and farming as main occupation significantly and positively affected the adoption of passion fruit while age was significant with negative effect. Private land ownership and access to extension services significantly and positively influenced the extent of adoption while age had significant negative effect. Further, this study revealed that passion fruit production was the more profitable farm enterprise than other comparable farm enterprises. The results mean more incentives and innovative drivers are necessary for crop diversification and substitution in Kenya and not sufficient for adoption of the new crops. Government and other stakeholders should formulate and implement effective policies related to promotion of adoption, production and marketing of new agricultural technologies.