In this study, it has been aimed to develop and apply an Internet-based smart soil maintenance system in order to increase productivity in automated irrigation and fertilization systems used in agriculture. The system we aim to develop performs irrigation and fertilization processes automatically with the lowest expenditure. Fertilization and irrigation can be done by controlling the humidity levels and pH values of the soil in fields and greenhouses, and communicating with the control centre via the Internet. The control centre nourishes the soil automatically on an optimal level with the stuff it needs by observing the soil values constantly with sensors. A system containing software and hardware used for this purpose has been designed to be manageable via the Internet. Communication between the systems used in this study has been maintained through Internet. After determining the necessary water and fertilizer amounts, the fertilization values have been adjusted in the liquid tank. After that, the mixture has been distributed to the soil automatically by valves used in each section of the field. Besides, by means of the web interface of the system, it has been possible to access the measured data easily in real-time.