As the human population rises, the demand for high nutritional foods, such as green vegetables, also increases. However, agricultural land, especially in urban areas, is increasingly narrowing. Hydroponics can be one of the solutions to answer this problem. In addition to complete nutrition, hydroponic plants also require appropriate media for root attachments, water absorption, and aeration. However, no studies have compared the growth of hydroponic plants using rockwool and sponge as affordable growing media. Therefore, this study aimed to determine the effect of local rockwool, imported rockwool, and sponge as growing media on the growth of spinach (Amaranthus sp.) and green lettuce (Lactuca sativa) using Deep Flow Technique (DFT). This study used a Completely Randomized Design with three treatment groups, i.e., three different growing media, for spinach and lettuce. At the harvest period, the number of leaves on each plant was counted, the crown fresh-weight was balanced, and the chlorophyll content was determined. Plant height was also measured for spinach. The results showed no significant differences in all observed parameters except for the crown fresh-weight of the lettuce. The crown fresh-weight of the lettuce grown on sponge media was found to be the lowest significantly (81.47 ± 9.50 g) among all treatment groups. Other hydroponic growing media’s influences can be investigated for further research, with additional growth parameters such as crown dry-weight, root fresh- and dry-weight, as well as the determination of plant phytochemical contents. Moreover, the composition of nutrients can also be further examined to reveal the type of growing media and nutritional formulations that are most optimum for hydroponic spinach and lettuce growth.