Nobuhiro SATO criticized that Konyo's sweet potato cultivation method was a 'Careless method' in his book "Six-step method in cultivating plants"and introduced high temperature and humidity seedlings as a harvest method at early time, in contrast to Konyo's method of planting the seed tuber directly on ground.
佐藤信淵はその著書『草木六部耕種法』の中で、昆陽の薩摩芋栽培法を「疎放なる作法」と批判し、昆陽の種芋を直接地面に植える方法に対して、高温多湿な苗代を作り早い時期に収穫する方法を紹介している。