As a result of the adaptation of plants to geographically different environments, there is a rich diversity of plant phenology in temperate and tropical climates. Recent scientific advances in this science offer numerous opportunities to study the basis of their adaptation to such environments. It is estimated that this recent knowledge on plant phenology with such varied perspectives (molecular, ecological, modeling, satellite, etc.) will help to understand how its natural selection led to the evolution of its regulatory mechanisms, particularly in ecosystems being affected by climate change. Relevant aspects on latitudinal gradient of plant phenology, the environmental factors underlying such phenological diversity, and the approach of integrated studies that can predict the future adjustment of plants in the face of climate change are reviewed.