Water hyacinth (Eichhornia crassipes) is a weed that is often found in waters both in rivers and in rice fields. Water hyacinth contains 78.47% organic matter, 21.23% organic C, 0.28% total N, 0.0011% total P and 0.016% total K, elements that are needed by plants (Ervina et al., 2018) ). water cabbage is a type of aquatic weed that grows floating and is commonly found in rice fields. Based on research conducted by Haryatun (2008) water cabbage contain 2.67% N, 0.30% P and 1.12% K.Based on the 2019 Decree of the Minister of Agriculture of the Republic of Indonesia concerning Minimum Technical Requirements for Organic Fertilizers, Biological Fertilizers and Soil Improvers, it is known that the quality standard for liquid organic fertilizers must have a macro nutrient content (N + P2O5 + K2O) of 2 - 6%. Judging from the description above, at least two combinations of organic matter are needed in the manufacture of liquid organic fertilizer so that the macro-nutrient content in liquid organic fertilizer can meet these quality standards. In this study, researchers will use a combination of water hyacinth and water cabbage. The planting medium used in this study was semi-solid agar. To determine the effectiveness of liquid organic fertilizer, rice (Oryza sativa) was used as a growth indicator.The purpose of this study was to determine the effect of applying liquid organic fertilizer (POC) from processed water hyacinth and watercress in agar growing media on the initial growth of rice plants (Oryza sativa).This study used a single factor complete randomized design (CRD) with five treatments and each treatment was repeated four times. Thus, 20 experimental units were obtained. The experiments were: Treatment factors: P0 = Without liquid organic fertilizer (POC), P1 = POC NASA 2.5 ml/liter, P2 = POC water hyacinth and water lily 2.5 ml/liter, P3 = POC water hyacinth and water hyacinth 5 ml/liter and P4 = POC of water hyacinth and water hyacinth 7.5 ml/liter. The parameters of observation were plant height, dry weight of plant canopy, and dry weight of plant roots. The results showed that the administration of POC water hyacinth and water lily 5 ml/liter showed a good response compared to other treatments.