Abiotic stresses are potent growth and yield inhibitors for horticultural crops. Phytohormone treatments will be a potential solution against abiotic stresses. Salicylic acid (SA), a phytohormone, is pivotal in enhancing plants and alleviating various abiotic stresses by modulating key physiological and biochemical processes. As an effective plant growth regulator, SA enhances morpho-physiological parameters, including plant height, root and shoot growth, fresh and dry biomass, photosynthetic pigments, and leaf area. Through its ability to regulate antioxidant enzymes and reactive oxygen species (ROS), SA minimizes oxidative damage, improves water use efficiency, and promotes photosynthetic efficiency. SA also interacts with other signaling molecules and phytohormones, influencing gene expression related to stress responses. For instance, exogenous SA has been shown to enhance drought and salinity tolerance by improving chlorophyll content, K+/Na+ ratios, mineral uptake, and antioxidant defense in crops. Additionally, SA application during heat and heavy metal stress regulates antioxidant activity, decreases malondialdehyde content, and enhances growth, as seen in crops. The combination of SA with other regulators, such as melatonin and silicon, further enhances stress resilience by improving nutrient uptake and reducing the accumulation of heavy metals. These findings emphasize SA’s potential as a critical tool for improving plant performance, resilience, and productivity under increasingly adverse environmental conditions, offering valuable strategies for sustainable agriculture.