The objective of this research was to determine the effect of the interaction of K fertilizer
and humic-fulvic acid application on the growth of Jicama plants. The research was carried
out in the experimental field of the Agrotechnology Study Program, Faculty of Agriculture,
Universitas Muhammadiyah Purwokerto, Karangsari Village, Kembaran Sub-district of
Banyumas Regency with an altitude of 85 meters above sea level. This research was
conducted from April to July 2021. The experimental design used was a Completely
Randomized Design ( CRD) with two factorials. The first factor is the dose of potassium
(P) fertilizer with three levels, namely : 0.35 g/polybag, 0.30g/polybag, and 0.25 g/polybag.
The second factor is fulvic humic acid (K), namely: 123 ml/polybag, 250 ml/polybag, 50
ml/polybag. From the observational data statistical analysis test variance level 5%, the
interaction between potassium fertilizer and humic acid had no significant effect on all
observed variables, namely dry weight of the hull, dry weight of tuber, fresh weight of
tuber, number of tubers, tuber volume.