The brain stores a large number of memories, which are recalled through external stimuli or spontaneously during memory replay, a process essential for memory consolidation. Memory storage has traditionally been attributed to excitatory synaptic plasticity and the effect of inhibitory plasticity on memory capacity and recall remains underexplored. To elucidate how inhibitory plasticity affects memory capacity and recall, we compare two inhibitory plasticity rules in spiking autoassociative networks: a homeostatic plasticity rule and a rule that maintains firing rate heterogeneity. Our results show that networks stabilized with homeostatic plasticity significantly outperform those with heterogeneous firing rates in both pattern completion and the spontaneous replay of unique embedded patterns. Furthermore, we demonstrate that the likelihood of a pattern being replayed depends on whether it forms an attractor state in the network. We thus equate the number of spontaneously reactivated patterns with the traditional concept of memory capacity and we present a novel approach to defining and studying how many patterns a network can store. These findings highlight the importance of inhibitory plasticity not only for stabilizing neural activity but also for enhancing memory storage and recall capability.