Abstract—Ashwagandha (Withania sominifera Dunal) is an imperative medicinal crop in herbal industry since time immemorial which roots are in commercial importance. This herb known for its ability to enhance the resistance to stresses, increases stamina and promotes general wellbeing. The changes in the plant growth and quality of the roots mainly depend on different agronomic practices coupled with stage of harvesting. Plants grown under organic and inorganic sources of nutrients were used up to twelve months of sowing for yield analysis and tubers were analyzed for its alkaloid, total fiber and withaferine A contents upto ten months. Highest values for all above phyto constituents were recorded in tubers of organically grown compared to inorganically fertilized plants except crude fiber content and at six months after sowing is the best stage for harvesting to obtain high quality tubers. This is an important study for biochemical standardization of Ashwagandha tubers in commercial processing.