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Barium titanate (BaTiO3) is a prototypical ferroelectric oxide exhibiting a structural transition between a tetragonal ferroelectric phase and a cubic paraelectric phase. While its equilibrium properties have been extensively investigated, the ultrafast electronic and structural dynamics that accompany this transition remain only partially understood. Here we investigate these processes using time-resolved high-harmonic spectroscopy in bulk single-crystal BaTiO3 driven by intense, ultrashort mid-infrared laser pulses. The harmonic emission shows pronounced anisotropic orientation dependence reflecting the tetragonal symmetry of the crystal. Following optical excitation, we observe transient modifications of the harmonic emission pattern together with the emergence of additional nonlinear wave-mixing signals. Remarkably, these signals persist far beyond the temporal overlap of pump and probe laser pulses. The long lifetime suggests the formation of a coherent excitonic polarization with a dephasing time significantly longer than that expected for a photoexcited electron-hole plasma. Changes in the anisotropic harmonic response indicate a transient reduction of the tetragonal distortion consistent with a photoinduced shift toward cubic-like symmetry. These results demonstrate the sensitivity of time-resolved high-harmonic spectroscopy to coupled electronic and structural dynamics in ferroelectric materials and reveal long-lived coherent excitations in BaTiO3.