We report on the growth of large pyrrolidine-based polyene single crystals from methyl ethyl ketone (MEK) solutions for nonlinear optical applications. The polyene crystals grown exhibit a suitable morphology and Surface roughness and good optical quality. We successfully demonstrated THz wave generation with as-grown polyene crystals. Although the crystal cut was not optimized and phase-matching conditions were not fulfilled, we achieved a similar or higher THz generation efficiency compared to the well-known inorganic ZnTe emitter crystals