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Four modes of NDVI changes, Mode α, Mode β, Mode γ and Mode δ can be classified due to three precipitation distribution types, A-, B- and C-type. In order to increase the probability of continuous growth of vegetation in a timely manner and to improve efficiency of precipitation, the probability of occurrence of α, β and δ Modes (these three changes are mainly for vegetation growth) should be increased as much as possible, and the vegetation grown of the β Mode is the best. In EGS, Type B of precipitation is not associated with δ Mode. In MGS, γ Mode increases rapidly while the proportion of the β Mode decreases, and the other modes disappeared. The reason that γ Mode increases rapidly in MGS may be excessive precipitation which keeps the soil moisture in a state of supersaturation, thus inhibiting the growth of desert vegetation. Type A most likely gives rise to γ Mode and β Mode, and Type C only cause δ Mode in EGS. In MGS, α and β Modes of NDVI are for Type A , while α, β and γ Modes are for Type C. Therefore, it can be investigated that Type B and Type A of precipitation are the optimum precipitation distribution type that can effectively maintain the trend of lush vegetation in EGS and MGS, respectively. [Display omitted] • Shortening time lags of NDVI responses to daily precipitation over time. • Classified three temporal distribution types of a precipitation process. • Different precipitation processes benefit availability of moisture for diverse stage. • Precipitation changes tend to impact NDVI changes given dry period of > 18 days. Vegetation in arid/semiarid areas in the northern hemisphere is highly sensitive to precipitation variability. Understanding the change of dryland vegetation and its response to spatiotemporal patterns of precipitation changes is critical to delve impacts of meteorological droughts on dryland vegetation. Based on the Normalized Difference Vegetation Index (NDVI) and precipitation data, we delineated the spatiotemporal pattern of trends of the arid/semiarid plant growth and its responses to daily precipitation changes in the northern Xinjiang. The results indicated several regular characteristics in the NDVI responses to precipitation at unequal time and spatial scales during the growing season, i.e. April-October. It identified shortening time lags of NDVI responses to precipitation over time. This study found for the first time that precipitation changes tend to impact NDVI changes given dry period length (DL) of > 18 days, and the effect of precipitation process was more significant. Three temporal distribution types of a precipitation process were classified, i.e. A-type or B-type precipitation process, which are characterized by two consecutive rainfall days with less or larger precipitation amount on the first day than the next day, and C-type precipitation process, which is characterized by three or more consecutive rainfall days. A- and B-type precipitation processes can benefit availability of moisture in the medium and early stage of the growing season respectively. Precipitation of 6.1–12.0 mm is the most favorable condition for the growth of desert vegetation. This study highlights multifarious vegetation responses to different precipitation processes and provides theoretical ground for ecological restoration and conservation in a changing environment across northern Xinjiang, China, and also in drylands in other regions of the globe. [ABSTRACT FROM AUTHOR]