| To investigate the effects of meteorological conditions on the growth, development, and yield of asparagus lettuce, a split-plot sowing experiment was conducted at the Huzhu Agrometeorological Experiment Station in Qinghai Province in 2024 and 2025 using the purple-leaf cultivar ‘Yousisheng No. 10’. Six sowing dates were set to systematically observe the developmental stages, stem length, stem diameter, fresh weight per plant, and the occurrence of meteorological disasters. Partial correlation analysis and path analysis were performed by integrating these observations with synchronous meteorological data. The results showed that low temperatures of -2 to -3 °C during the seedling stage had little impact on the lettuce. Sowing date significantly affected the growth process and yield formation, with the whole growth period shortening as sowing was delayed. The mean temperature during the whole growth period was very significantly positively correlated with stem length but very significantly negatively correlated with fresh weight per plant. The maximum temperature from the stem swelling stage to maturity was also significantly negatively correlated with fresh weight per plant. Path analysis further identified high temperature during the late growth stage as the key factor limiting yield. In conclusion, the purple-leaf asparagus lettuce ‘Yousisheng No. 10’ is sensitive to high temperatures. Sowing in early spring, specifically in mid-April,?is conducive to achieving higher fresh weight per plant and superior commercial quality, while?sowing in mid-July under summer multiple cropping conditions?can mitigate the adverse effects of high temperature. These findings provide a scientific basis for optimizing sowing dates and climate-adaptive cultivation of cool-season vegetables on the plateau. |