Rapid urbanization and industrialization result in increased demand for infrastructures and housing worldwide. Therefore, the consumption of construction materials continues to rise. Cement is a common component used in the manufacture of concrete and mortar. However, the cement manufacturing process severely influences the environment, which causes the release of large amounts of carbon dioxide into the atmosphere. In addition, the agriculture and plantation industries are primary economic pillars in many countries, particularly developing countries, including Indonesia, India, and China. However, it cannot be denied that this industry severely impacts the environment, as it generates biomass waste that cannot be efficiently managed. This study investigates and examines alternative materials for cement replacement in mortar production. This research evaluated the fresh and hardened properties of mortar on the laboratory scale. In addition to destructive tests, ultrasonic pulse velocity (UPV) and rebound hammer tests were also conducted. The fresh properties test consisted of a slump flow, while the hardened properties test included compressive strength, porosity, water absorption, and mass loss. It can be concluded that each waste has characteristics that make it a suitable replacement for cement in mortar production. The results indicate that 10% of agricultural waste can be substituted for cement to generate a mortar with comparable compressive strength to normal concrete, thereby reducing cement consumption by 10%. In terms of hardened properties, the increasing amount of waste results in a lower mass density hardened mortar compared to normal mortar, so the use of this waste has the potential to produce a lightweight material. Thus, employing sufficient amounts of agricultural waste as a cement substitute produces mortar with beneficial characteristics and reduces the use of cement to produce sustainable construction materials.