The purpose of this research is to examine whether, and how, an asynchronous online learning community pedagogical approach can address students' challenge of integrating disciplinary ideas into an interdisciplinary understanding. A quasi-experimental research design was conducted in which 51 undergraduate students were allocated into two groups who learned a similar asynchronous online interdisciplinary course. The two groups differed in the learning mode in which the courses were designed and taught: a learning community (LC) mode for the experimental group, versus an individual learning (IL) mode for the control group. We used a designated rubric to compare the quality of students' interdisciplinary understanding, as expressed in a synthesis essay each student wrote. Findings show that students' abilities to synthesize disciplinary ideas were significantly higher in the LC group. Since synthesis of disciplinary ideas is the goal and essence of interdisciplinarity, we view these findings as indicating a higher quality of interdisciplinary understanding among the LC mode students. This work demonstrates and delineates the potential of the LC approach to promote the development of interdisciplinary understanding in higher-education asynchronous online environments.