Population growth and urbanization in the Greater Jakarta area have led to the conversion of agricultural land into residential areas, industrial areas, and other infrastructure. This has caused a decline in local vegetable production, resulting in increased dependence on vegetables from outside the region. To address this issue, hydroponic cultivation can be a solution. Hydroponic cultivation is a method of growing plants using water as the growing medium. However, this hydroponic system requires regular monitoring of environmental parameters. This poses a challenge for urban residents who are predominantly engaged in work and activities outside the home. This study proposes a hydroponic plant monitoring and control system integrated with Internet of Things (IoT) technology. Lettuce plants are the cultivated crop, and the ESP32 microcontroller serves as the system's central unit. This system can automatically monitor water temperature, air temperature, air humidity, and nutrient content parameters,
control nutrient content parameters, and display data on the Blynk platform to monitor plant conditions remotely. Test results showed that water temperature measurements had a data difference of ±1°C with a relative error of 1.5. Air temperature measurements had a data difference of ±1.5°C with a relative error of 0.6. Air humidity measurements had a data difference of ±1.5% with a relative error of 1.6. Nutrient content measurements had a data difference of ±3ppm with a relative error of 0.41. And water level measurements had a data difference of ±0.16cm with a relative error of 1.7