A system for monitoring plants in a greenhouse, the system comprising: a plurality of weighing units, the weighing units distributed in the greenhouse, each of the weighing units is attached to a single plant or group of plants and comprising means for weighing the plant or group of plants, the weighing units are trellising from an elevated wire at one end and connected to the top end of the plant or group of plants at the opposite end a communication network comprising means for communicating the weight of the plant or group of plants from the weighing units to a central unit and a central unit, the central unit comprising means for receiving, storing, processing and analyzing data received from the weighing units through the communication network.
