For a year-round supply of high-quality garlic, a technological system that combines the post-harvest curing of bulbs and long-term storage is essential. For long-term storage after harvesting and curing, storage at a subzero temperature effectively suppresses germination and rooting. However, after being delivered from a storehouse through distribution and sales to consumers, instances of “concavities on the surface of scales” of garlic bulbs have been witnessed when kept at ambient temperature. As a method of suppressing the occurrence of concavities, we focus on curing after harvesting. We confirmed that the incidences of concavities after storage at subzero temperatures are greatly reduced by introducing a tempering method that ventilates hot air during the daytime and ambient temperature air overnight. And based on the demands of growers, we showed how the tempering method can be applied at production sites. These results are summarized in the “Post-Harvest Processing Manual for a Year-Round Supply of Garlic” and utilized at production sites.