A modular soilless garden system for supporting a plant root cultivation medium (such as a substratum mat). The system comprises a platform with a subsurface temperature regulation network. The network facilitates passage of a gas or a liquid to regulate the temperature of the plant roots hosted in the cultivation medium. A plurality of foundations connect end to end to form the platform. Two circulation manifolds connect to the terminal ends of the platform to interconnect the distinct subsurface fluid passages.
