ABSTRACT The aim of this study was to assess how microclimate variables and irrigation affect the growth of sugarcane. The experiment was conducted using the VAT90-212 cultivar in the Semi-arid region of Brazil. The microclimate was monitored and by quantifying the irrigation depth. Nine campaigns were carried out in the field to collect morphological and biomass data. The data were subjected to descriptive statistics, so as to generate the mean values and/or sum between the campaigns. Using the correlation coefficient, the extent, sign and significance of the relationship between the response and explanatory variables were evaluated. The direct or indirect effects of the explanatory variables on the response variables were identified by path analysis. There was a significant correlation between microclimate variables and the morphological and biomass variables of the sugarcane, with a strong contribution from the intercepted fraction of the photosynthetically active radiation, the wind speed and soil temperature. The negative correlation with irrigation suggests that excess water impaired the growth dynamics of the crop. It is concluded that the growth of sugarcane is closely related to its capacity to intercept radiation, to the wind, thermal regime of the soil and irrigation management.