Plants adapt their morphology in response to variable environmental conditions such as nitrate availability, drought, and temperature shifts. Three crucial aspects to this developmental plasticity are the control of initiation, identity and activity of meristems. At the cellular level, the activity of meristems is controlled by balancing self-renewal in stem cells, amplifying divisions in their daughter cells, and cell differentiation. Recent studies in plants have uncovered transcription factors regulating meristem activity at cellular resolution, and regulatory networks that couple these factors with phytohormone signalling for global plant growth regulation. Here, we highlight selected recent advances in our understanding of the multidimensional transcriptional networks that regulate meristem activity and discuss emerging insights on how a selection of environmental cues impinges on these networks.