The 8th general of the Edo bakufu (Japanese feudal government headed by a shogun) Yoshimune TOKUGAWA had already ordered Konyo to cultivate the known sweet potato as an emergency crop at the famine in West Japan, and make trial pieces in the Koishikawa Medicine Garden (Koishikawa Botanical Gardens), Makuwari-mura village in Chiba District of Shimousa Province (present Makuhari, Hanamigawa-ku Ward, Chiba City, Chiba Prefecture), and Fudodo Village in Yamabe County of Kazusa Province (present Kujukuri-cho, Sanbu-gun, Chiba Prefecture).
江戸幕府8代将軍徳川吉宗は、すでに西日本では飢饉の際の救荒作物として知られていた甘藷（サツマイモ）の栽培を昆陽に命じ、小石川薬園（小石川植物園）と下総国千葉郡馬加村（現在の千葉市花見川区幕張）と上総国山辺郡不動堂村（現在の千葉県山武郡九十九里町）とで試作させている。