The influence of different mulching measures on soil moisture, soil temperature, and crop growth was investigated during the jujube growing season in rain-fed jujube orchards using micro-plot experiments. The mulching treatments included clean tillage (CT, control treatment), jujube branches mulching (JBM), and white clover planting (WCP). The results revealed that: (1) The average soil moisture content of JBM was greater than that of CT by 3.76% and 2.34%, respectively, during the 2013 and 2014 jujube growth periods, and its soil water deficit was minimal in each soil layer from 0 to 70 cm. WCP had the greatest soil water deficit. The average soil moisture content of the 0–70 cm soil layer in WCP was 3.88% and 5.55% lower than that in CT during the 2013 and 2014 jujube growth seasons, respectively (p < 0.05). (2) JBM had the highest annual average soil moisture content in each soil layer from 0 to 70 cm, followed by CT, while WCP had the lowest. White clover and jujube competed for water in the 20–40 cm soil layer, and JBM had the lowest variation in soil moisture. (3) Mulching with jujube branches and planting white clover could both control the temperature of the 0–25 cm soil layer and narrow the daily temperature range, with JBM being the least affected by air temperature. (4) Jujube’s leaf area index and stem diameter increase in JBM were both significantly greater than in CT and WCP. In conclusion, using pruned jujube branches as surface mulch is appropriate for rain-fed jujube orchards because it can preserve soil moisture, regulate soil temperature, and promote jujube growth.

The implementation of the “Returning Farmland to Forest” project in the loess hilly region of China has led to the establishment of large-scale economic forests, which have become the dominant industry driving local economic development. However, the region faces challenges such as drought, water shortages, and an uneven distribution of precipitation, which have a severe impact on the growth of economic forests, including jujube trees. Water stress significantly reduces yield and efficiency, posing a threat to the sustainable and healthy development of jujube ecological and economic forests. Therefore, this study aimed to address these issues by implementing straw mulching (SM) and jujube branch mulching (BM) measures in the mountainous jujube economic forests. Through long-term monitoring and statistical analysis, the study investigated the effects of different mulching treatments on soil moisture and soil temperature. The research findings reveal that both SM and BM significantly increased soil moisture in the 0–280 cm soil layer during the jujube growing season (p < 0.05). In both normal precipitation (2014) and drought (2015) years, SM increased average soil moisture content by 5.10% and 4.60%, respectively, compared to the uncovered treatment (CK). SM also had a positive impact on the soil moisture content in each layer of the soil profile. However, BM only increased soil moisture content in the 40–100 cm and 220–280 cm soil layers. Additionally, SM and BM reduced the variation of soil moisture, with SM showing a more significant effect in regulating soil moisture and achieving more stable moisture levels. During the jujube growing seasons in 2014 and 2015, SM and BM decreased soil temperature in the 0–10 cm soil layer. The temperature difference compared to CK decreased with increasing soil depth. SM had an overcooling effect, while BM reduced the temperature before the fruit expansion period and maintained warmth afterward. Both SM and BM also reduced the daily range and variation range of soil temperature, with SM having a more pronounced effect. The temperature of the 0–20 cm soil layer exhibited the strongest correlation with air temperature, and SM showed the weakest response. In conclusion, adopting straw mulching and jujube branch mulching in rain-fed jujube orchards in the loess hilly region not only saves materials and reduces costs but also contributes to water retention and temperature regulation. Straw mulching, in particular, plays a more significant role in moisture retention and temperature regulation and is advantageous for soil management in rain-fed jujube orchards. These research findings provide a scientific basis for optimizing water and heat management in orchards with limited water resources.

Water shortage is the main bottleneck restricting the sustainable development of rain-fed jujube (Ziziphus jujuba Mill.) orchards in the loess hilly region of China. Given the effect of mulching on soil moisture conservation, straw mulching (SM) and jujube branch mulching (BM) were applied to a rain-fed jujube orchard in this study. Soil moisture dynamics, soil water storage, water consumption, and soil moisture attenuation after typical rainfall under SM, BM, and clean tillage (CT) were studied. The results showed the following: (1) The 0–60 cm soil layer was the seasonal fluctuation layer of soil moisture under SM, BM, and CT in both the normal precipitation year and the dry year studied. The moisture contents of the 0–60, 60–160, and 160–280 cm soil layers under SM and BM were higher than that under CT in the three experimental years studied, and SM showed the most obvious effect of increasing soil moisture. (2) SM and BM showed a significant soil water storage effect in all of the jujube growth stages, and SM had a better water storage effect than BM. (3) SM reduced the amount of water consumption by 94.3, 60.8, and 121.3 mm compared to CT in the whole jujube growth period in 2014, 2015, and 2016, respectively. The amount of water consumption of BM decreased by 34.8 and 31.0 mm compared to that of CT in the whole growth period in 2014 and 2015, respectively. (4) CT had the maximum soil moisture loss rate under continuous drought after rainfall. The soil moisture loss rate of CT was above 37.3% on the eleventh day after typical rainfall in 2014, 2015, and 2016. With the extension of drought, the soil moisture loss rate under SM increased slowly. This study suggests that SM is the best mulching measure for rain-fed jujube orchards, and pruned jujube branches can also be used for in situ mulching to obtain a certain moisture conservation effect.