This paper presents results of an experimental study conducted to evaluate the combined effects of prolonged mixing time, late water inclusion, and variations in total water content on the long-term compressive strength of controlled low-strength material (CLSM). Long-term strengths refer to strengths measured after 600 days of curing. To evaluate strength development in moist ground conditions, sampled specimens were continuously cured in water. The main aim of the research was to determine the effects of mixing and water content variables on the long-term strength development of the immersed CLSM mixture as measured by unconfined compression testing. Findings are discussed.