Harvest occurs after the tops have fallen and are very dry. The cloves should be firm to the touch. Grades include U.S. No. 1 and unclassified, and are based primarily on external appearance and freedom from defects. The variety of garlic affects potential storage life, and the recommended conditions for commercial storage depend on the expected storage period. However under these conditions, bulbs will eventually become soft, spongy and shriveled due to water loss.
Good airflow is also necessary to prevent any moisture accumulation.
Under these conditions garlic can be stored for more than 9 months. Garlic will eventually lose dormancy, signaled by internal development of the sprout. Garlic odor is easily transferred to other products and should be stored separately. High humidity in the storages will favor mold growth and rooting. Mold growth can also be problematic if the garlic has not been well cured before storing.