Phenotypic plasticity may be one of the crucial factors determining the success of plant invasions in diverse habitats, particularly for those very noxious species with low genetic diversity such as Alternanthera philoxeroides in China. Although phenotypic responses of clonal plants to different light intensities, soil water or soil nutrient availabilities have been extensively studied in the past decades, little is known about how climate warming affects morphological plasticity of plants, particularly invasive plant species. Climate warming is among the serious threats to biodiversity and ecosystem functions, thereby raising concerns over its ecological consequences. Increasing evidence suggests that climate warming is asymmetric and the magnitude of nighttime minimum air temperature may increase greater than that of daytime maximum air temperature. Recent studies have shown that climate warming is likely to have significant effects on plant photosynthesis and respiration. Consequently, it is necessary to understand how terrestrial plants respond to differential warming scenarios, which can help us better predict their response under these conditions. We conducted a simulated warming experiment at Chengdu in which the invasive clonal herb Alternanthera philoxeroides was subjected to each of the eight combinations consisting of serving stolons (i.e. serving and intact stolons) and simulated warming (i.e. day-warming, night-warming, daily warming, and control treatment). This experiment lasted three months. At the end of the experiment the morphological traits of all experimental materials were determined. Overall warming treatment increased air temperature by about 2 ℃, and the warming magnitude was variable depending on specific weather conditions. Our central object was to test how A. philoxeroides plants responded to different warming treatments morphologically. Across all three warming treatments, physically severed connection significantly suppressed the growth of A. philoxeroides fragments primarily through reducing the total stolon length and average stolon length per ramet. In contrast, simulated warming per se did not exhibit significant effects on these indices mentioned above. When the three warming treatments were considered separately, they had contrasting consequences for the morphological traits of A. philoxeroides. Specifically, day-warming and daily-warming did not confer significant impacts on both severed and connected fragments in terms of total stolon length and average stolon length; night warming significantly elongated the total stolon length and average ramet length of A. philoxeroides with connected stolons, but did not affect those of A. philoxeroides with connected stolons; all the three warming scenarios did not affect ramet numbers of both fragments. These findings are relatively preliminary, but they have some potential implications. First, our results suggest that A. philoxeroides fragments may have strong tolerance to the 2 ℃ warming and differentially respond to these projected warming scenarios. Second, for A. philoxeroides fragments commonly growing in disturbed habitats, night-warming may facilitate their growth and clonal integration through photosynthetic overcompensation, thereby enhancing their invasion by rapidly spatial expanding along the horizontal direction and occupying favorable habitats. Third, day-warming and daily warming may have no obvious impacts on the morphological characteristics of those fragments of A. philoxeroides. Finally, modeling plant responses to climate warming should consider warming timing. Additionally, these findings also provide an initial indication that more efforts should be paid to uncover response patterns of plants to different warming scenarios and how these responses influence community composition and structure, and ecosystem functions.