Embryonic organizers are multicellular domains that govern the differentiation of adjacent cells by secreting diffusible signaling molecules. The vertebrate tail organizer functions within a flux of tailbud mesodermal progenitors and ectoderm to direct the elongation of the developing spinal column. Using pharmacological and localized transgenic perturbations, 4D live confocal imaging of the zebrafish embryo, cell tracking and systematic analysis of cell motion, we characterized role of the organizer in tailbud tissue mechanics. Cells transiting the organizer express the posterior homeobox gene eve1 as well as bmp2b and bmp4 and cease expressing these genes when they exit the organizer. Surprisingly, localized perturbation of the organizer increases the heterogeneity in cell motion many cell diameters upstream of the organizer where Bmp signaling is undetectable. We find that this long-range effect is mechanical and not via cell signaling. This mechanical information, propagated via relay through local cell-cell repulsion, can project more efficiently than diffusible signals and thus extend the organizer’s sphere of influence beyond that of a canonical morphogen gradient. Mechanical information flow may represent a general mechanism for rapid and long-range orchestration of embryonic morphogenesis.