The impact of storage duration on the geotechnical properties of soils is a recurring issue in the field of geotechnical engineering. Due to the lack of previous research addressing this topic, an experimental study was conducted to evaluate the variation of these properties over time. Undisturbed samples of silty and organic soil from Quito, Ecuador, were obtained. These samples were subjected to unconfined compressive strength (UCS) and moisture content (MC) tests at various intervals (1, 3, 7, 14, 21, 28, and 56 days). Results revealed a significant correlation between MC, UCS, and modulus of elasticity (ME). A progressive increase in UCS and ME was observed as MC decreased, with peak values observed to occur between 20 and 30 days. These findings suggest that matric suction plays a predominant role in increasing cohesion and, consequently, UCS. Therefore, it is concluded that the time elapsed between sample extraction and testing is a critical factor influencing the preservation of MC and, hence, the accurate assessment of the soil’s mechanical properties.