Pak Choi (Brassica rapa L.) is a highly beneficial leafy vegetable due to its
content of essential vitamins, minerals, and fiber necessary for human health and
improved quality of life. However, the nutritional content and benefits of Pak
Choi are not matched by the production obtained from traditional agricultural
fields. One method to support the growth and increase production of Pak Choi
plants is through hydroponic cultivation. The relatively high cost of AB Mix has
led to the need for large-scale businesses to seek alternative materials to replace
AB Mix or reduce its concentration by combining it with more affordable Liquid
Organic Fertilizer (LOF). One of the options is liquid organic fertilizer based on
the waste from boiling soybeans for tempeh production. This research aims to
determine the effect of applying different concentrations of Liquid Organic
Fertilizer (LOF) derived from soybean boiling liquid waste, with varying time
intervals, on the growth and yield of Pak Choi (Brassica rapa L.) plants. The
research design used is a Completely Randomized Design (CRD) consisting of
two factors: concentrations of LOF from soybean boiling liquid waste, with 6
levels (P0: Control/water; P1: LOF 75 ml/L; P2: LOF 100 ml/L; P3: LOF 125
ml/L; P4: LOF 150 ml/L; P5: AB Mix), and LOF application intervals, with 3
levels (W1: 1 week; W2: 2 weeks; W3: 3 weeks); each treatment was replicated
three times. The results of the research show that applying a concentration of 125
ml/L of LOF derived from soybean boiling liquid waste and applying LOF with a
3-week interval significantly affected the growth and yield of Pak Choi plants.
The best treatment that influenced the growth and yield of Pak Choi plants was
observed in treatment P2W3, with the application of 100 ml/L LOF and a 3-week
interval.