For two growing seasons, Ovid Napa Valley, a vineyard in St. Helena, Calif., has been using a wireless sensor network to grow grapes it hopes will one day yield more delicious wines than ever before.
One challenge of winemaking is determining just the right amount of irrigation to appropriately deprive grapevines of water, an unintuitive art needed to make good wine. Traditionally, “lots of irrigation and vineyard practices are based on gut feeling,” says Austin Peterson, assistant winemaker at the Ovid vineyard.
“Without scientific data guiding how we irrigated, we often experienced excess vigor” in the vineyard’s plants, he says. Excess vigor leads to under-ripe fruit, larger berries and dilution, which he explains are undesirable characteristics.
Automated methods of measuring water status in the vines, while helpful, still required much walking around the vineyard. Random readings often didn’t account for continually changing environmental and soil conditions.
In 2007, Ovid teamed with vineyard management startup Fruition Sciences, which was devising a new way for winemakers to instantly access data by computer about the vines’ water-evaporation levels relative to environmental conditions. Together, they began using sap-flow sensors in combination with an IP-based PhyNet wireless sensor network from Arch Rock.
The sensors measure the amount of water leaving the plant and send the measurements over the wireless network to remote computing equipment, where it is correlated with temperature, humidity, wind speed and solar radiation data. From this data, the Fruition system builds a “stress profile” for vines, allowing winemakers to make fast and accurate decisions about the volume and timing of their irrigation.The sap-flow sensor network emulates having someone in the vineyards all the time taking readings but without the labor and without sacrificing leaves that would normally have to be cut. Based on the data, “we have a much better understanding how vines respond to irrigation,” says Peterson. “When we moved to a schedule of deeper, less frequent irrigations, the vines would regulate themselves much better and could withstand heat spikes.”
Peterson said he already has a sense of the fruit’s improved quality in the fermentation tank. In terms of taste, weight and aromatic intensity, the revamped irrigation practices already seem to be yielding improvements, he says.