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Abstract. To improve the management of variable rate irrigation (VRI) system and make full use of rainfall in semi-humid climate, different irrigation management methods were evaluated to quantify their effects on maize growth parameters and their spatial variability during the 2016 and 2017 seasons. The three irrigation management methods evaluated were the soil-water balance modeling (SWB), measured soil water content (SWC), and the combination of soil-water balance method and rain forecast (RF) in the next three days. These irrigation treatments were implemented over four management zones delineated with available soil water holding capacity and were managed with the same irrigation trigger points of 70% of field capacity. The rain-fed treatment was also set in each zone with no additional application except for seedling emergence and aiding fertilization (35 mm in the 2016 season and 70.3 mm in the 2017 season). The results indicated that the mean irrigation water in the SWC treatment of the two seasons was 22% and 20% less than that in the SWB and RF treatments, respectively. The minimum yield was obtained in the rain-fed treatment in both seasons. Significant difference in plant height, LAI, and yield among irrigation management methods was only obtained in the 2016 season with uneven temporal distribution of rainfall. Both the LAI and yield were significantly different among management zones in the 2017 season with small rainfall. Irrigation management methods had minor effect on the spatial