Real-time mapping of plant water stress at vineyards and orchards enables optimal irrigation control that can produce high quality fruit and target yield of grapevines and tree fruits. This project used infrared thermography onboard a Unmanned Aerial Vehicle (UAV) to map high-resolution plant water stress over a commercial vineyard and an orchard in Victoria. Innovative blending of visible and near infrared imagery with the thermography accurately mapped water stress for individual grapevines and fruit trees. This project demonstrated capability of UAV-borne thermal infrared sensing in mapping high-resolution crop water stress over horticultural crops. The demonstrated technology can be readily applied to upscale the conventional ground-based water stress measurements to the large-scale horticultural enterprises accurately.