A hydrothermal processing route was used to produce anisotropic submicrometer particles of potassium niobate-tantalates and pure potassium niobate. Piezoelectric activity, switching polarization, and piezoelectric hysteresis loops were observed in these ferroelectric perovskite nanorods by means of AFM assisted detection of induced piezoelectric vibrations. Both lattice and domain wall contributions to the piezoelectric response were evidenced.