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Lime mortars are among the oldest type of building materials; their use is attested with various receipts through countries involving the use and the exploitation of different raw materials. In India organic additives such as plant and animal extracts are attested in ancient receipts credibly added to improve their technical performances. In fact, this technological expertise has been transmitted thanks to oral tradition and is nowadays partially still used; herbs, fruits and natural extracts were mixed in water, fermented for few days and the fermented organics along with water were added to the mortar mixture. Nevertheless, the role of organics in improving material properties is still not completely understood; preliminary studies revealed that the interaction of carbohydrate, protein and fat in organics with lime matrix determines a forced carbonation and the precipitation of newly phases (carbonate polymorphs and oxalates), resulting in enhanced mechanical and physical properties. Several factors as type of organics, lime/additive ratio, organic lime/aggregate ratio, curing time and fermentation times seems to critically influence the final properties.