Dataset obtained from a fully-instrumented experimental urban street canyon, located on a research site in Montpellier (France, Mediterranean climate) and monitored between July 21st, 2023 and July 31st, 2024. This east-west canyon consists of two parallel concrete walls (height 2.3 m, length 12 m, width 5 m). Three nearly adjacent planters (height 0.9 m, length 2.3 m, width 0.8 m) are aligned along its inner north wall and contain climbing plants of the Lonicera japonica specie. Three other nearly adjacent planters (height 0.9 m, length 2.3 m, width 1.1 m) are aligned along its inner south wall and contain shrub plants of the Abelia grandiflora specie. Each planter is equipped with an equal number of 11 soil sensors but different arrangements, to measure volumetric water content (4), matric potential (2) and temperature (5), collecting data every 10 minutes. Drip irrigation was used and each series of planters received identical irrigation amounts but the irrigation strategy changed several times, to monitor the impacts of irrigation on the overall water balance of the soil-plant-atmosphere system, especially on the local microclimatic variables. A dense network of 102 variables, for wind direction (1) and velocity (1), air temperature (64) and relative humidity (15), radiation (5), globe temperature (15) and pluviometry (1) was therefore installed across the canyon, all in the same horizontal plane located 1.3 m above the ground, which is a normalized measurement height for the determining variables involved in "thermal comfort", collecting data every 30 seconds. All soil-air data were distributed between 5 data loggers, each gathering raw data for air and soil in separate tables. Additionally, leaf density and leaf area index measurements were conducted, in 2023. This dataset is potentially valuable for (i) understanding the spatiotemporal dynamics and interplay between thermal, radiative and aerodynamic processes in vegetated urban canyons, (ii) identifying methodologies to detect the impact of different irrigation strategies on the microclimatic variables, (iii) validating numerical models of microclimate in the field of CFD-Computational Fluid Dynamics, and (iv) documenting then mitigate the effects of urban heatwaves, via appropriate management of urban water resources. Finally, this experiment is the first to address the potential impact of different plant types and irrigation regimes on the microclimatic variables, thus on urban thermal comfort indices that aim to express the temperature felt by the individuals in urban scenes.