In this paper, we propose the use of ad-hoc scrubbing sequences to improve memory reliability. The key idea is to exploit the locality of the errors caused by a Multiple Cell Upset (MCU) to make scrubbing more efficient. The starting point is the MCU distributions for a given device. A procedure is presented that uses that information to determine an ad-hoc scrubbing sequence that maximizes reliability. The approach is then applied to a case study and results show a significant increase in the Mean Time To Failure (MTTF) compared with traditional scrubbing.