Phenotypic plasticity has become a core concept in ecological evolutionary developmental biology ("eco-evo-devo"). This is due, to a large extent, to the major contribution of plant plasticity studies. However, the causes and consequences of phenotypic plasticity remain poorly understood. Herein, we summarize the development of research on phenotypic plasticity from an integrated perspective, including research contents and approach and brief history, with a focus on research progress and future directions. Modern plasticity research is laid on the foundations of studies that delineated the evolutionary significance of plasticity in plants. We describe the phenomenon of plant plasticity and discuss its genetic basis and evolution before exploring the underlying developmental mechanisms, associated growth and adaptation strategies, and ecological consequences. Future plasticity studies should be based on understanding and evaluating phenotypic plasticity and its adaptability from a new perspective, and closer attention should be paid to the complex network of environmental factors and plastic responses that operate under natural conditions. We conclude that understanding the eco-evolutionary implications of phenotypic plasticity should remain the emphasis of future research.