Plantain (Musa paradisiaca) is a climacteric fruit with high endogenous ethylene production, which accelerates ripening and limits shelf life, especially during transport and exportation, leading to significant losses for producers and distributors. This study evaluated the effect of gibberellic acid (GA₃) and zeatin (Zea) on delaying the ripening of Hartón plantains grown in Colombia. The goal was to assess whether these plant regulators could delay physicochemical changes under simulated cold chain conditions. A completely randomized design was used with nine treatments, plus a control, each with five replicates. Fruits were stored at 11 ± 2 °C and 75% relative humidity for 25 days. Pulp firmness, soluble solids, titratable acidity, pH, starch, chlorophyll, carotenoids, total polyphenols, and polyphenol oxidase activity were assessed. The combination of GA₃ + Zea was effective in preserving firmness, maintaining starch and chlorophyll content, and limiting increases in soluble solids and polyphenol oxidase activity associated with senescence. This delayed ripening did not affect structural integrity or caused oxidative stress. Combined application of GA₃ and Zea is a low-cost and effective strategy to extend the shelf life of plantains for export, benefiting the tropical agri-food chain. This approach offers a practical alternative for maintaining fruit quality without the need for costly preservation technologies.