We present an IoT platform specifically developed to manage the use of water in the production of crops typical of Mediterranean geographic area. A large number of innovative sensors able to measure the water content and, thus, the hydration condition of grapes is deployed in the vineyard. The sensing mechanism is based on the transduction of relevant parameters acquired directly from the plant and not, as usually done, from the environment (e.g. soil). The sensor data are collected by a set of sensor nodes able to send data over long distances to a central hub which uploads the data to the cloud making the remote monitoring of the field possible. Trained operators will, thus, be able to implement irrigation strategies based on the actual state of the plant sampled with a high temporal and spatial density. This technological platform makes possible the implementation of deficit irrigation practices useful to save water and optimize production but also to properly drive the final characteristics of the grapes and of the wine. The platform requires minimal maintenance and its installation does not interfere with regular farming activities.