Soil salinization is a growing global challenge that limits crop productivity, compromises soil health, and threatens food and feed security. For example, alfalfa (Medicago sativa), a major forage legume valued for its nutritional quality and ecological benefits, remains vulnerable to salt stress. Conventional approaches, including breeding, genetic engineering, and agronomic amendments, have delivered incremental progress but face limitations in scalability. Increasing evidence highlights that alfalfa enhances nutrient acquisition and stress tolerance through interactions with rhizosphere microbes. In this Opinion, I discuss recent insights into how salt stress regulates plant-microbe symbioses and propose that fostering beneficial root-associated microbiomes represents a promising strategy to improve nutrient use efficiency and environmental resilience. Such microbiome-informed approaches could open new avenues for enhancing crop yield, quality, and sustainability under saline conditions.