Abstract: A method of preparing a flowering plant product in hypobarically- and hypoxically-controlled atmospheres is disclosed. The method includes providing a simulated high-altitude controlled atmosphere (SHACA) room having a chamber, a plant support structure disposed within the chamber, and a microclimate control system operable to establish and maintain within the chamber a simulated high-altitude environment having an oxygen (O2) partial pressure of less than 20 kRa and, optionally, an overall pressure of less than 97 kPa. The method also includes disposing a flowering plant on the plant support structure, and exposing the flowering plant to the simulated high-altitude environment within the chamber. A simulated high-altitude CA room for cultivating and processing flowering plants in a hypobaric and hypoxic atmosphere is also provided.