Cultivated land is indispensable for promoting sustainable socioeconomic development. Therefore, investigating crop growth is essential for ensuring the stable utilization of cultivated land. This study assessed the spatial and temporal variations in crop growth across hydrological years and investigated the mechanisms linking the temporal distribution of precipitation to crop phenological responses via an integrated analysis of the MODIS EVI and daily precipitation datasets (2002-2020). The findings indicated significant interannual variability in precipitation throughout the spring maize growing season, with only 23.33 % of the years classified as normal. Spatially, crop performance was better in the eastern and southern regions than in the western and northern regions. Crucially, the alignment between precipitation timing and crop phenological stage emerged as a more significant factor than total precipitation. When the timing of water availability mismatches crop water demands, even high precipitation levels may fail to support optimal growth. To increase water use efficiency, adaptive strategies are proposed: prioritizing water allocation during key growth stages, adopting diverse irrigation approaches, and maintaining water conservancy infrastructures. These outcomes are crucial for promoting the sustainable utilization of cultivated land and safeguarding ecological security in semiarid areas.