While the debate continues about who actually made Arizona’s first wines, one fact rings true --- “Wines in Arizona have gotten much better than they used to be,” according to Phil Asmundson, owner of the contemporary precision agriculture Deep Sky Vineyards in Willcox.

Soil scientist Dr. Gordon Dutt is given credit for planting the first experimental vineyard on the Babocomari Ranch in Southern Arizona in the early 1970s, an experiment that evolved into Sonoita Vineyards where the first commercial crop was planted in 1979 and the winery opened in 1983.

Avid historians say savoring the juice of sun-sweetened grapes goes back several centuries when Spanish conquistadors trekked across Arizona and discovered wild grapes growing along rivers and streams.  It was less suitable for wine than the European species, but better than nothing until Mission grapes --- fruit grown in mission vineyards and used for the Holy Sacrament --- were cultivated in Southern Arizona’s rolling high country.  By 1700, Jesuit priests were writing back to Rome that “We have good vineyards to make wine for the masses.”

That was then, this is now and Asmundson and wife Kim have brought science and sensors into play.  “When growing experience is combined with real-time data collected from the plants themselves, precision agriculture can be a game changer,” says the company owner.

The 'grape bug'

Retiring at age 50 from a technology industry where he spent his life on airplanes --- “9 million miles on three airlines,” he remembers --- “Kim and I went to South America to taste some great wines.  We got a bit tipsy and bought a small vineyard in the Malbec region of Argentina.  We had the grape bug, we were hooked.”

On their return to Arizona, they realized the similarities between the two locations --- similar soils, similar high temperature amplitude, underground aquifers --- and began to look in their own back yard, ultimately purchasing 20 acres in 2009.  “We were the first in the state to plant Malbec,” he says. 

Deep Sky has now expanded to plant Rhone varieties of Viognier, Grenach, Mouvedre, Syrah, Petit Syran, and Counoise, all of which benefit from Arizona’s sunshine and terroir.  And because Willcox is, in Phil’s words, “So far from civilization that wagon trains still come through there…a great place to grow grapes, but hard to establish a business,” they purchased another 10 acres in nearby Elgin wine country and opened a tasting room there in 2017.

Having no experience at wine growing, the learning curve was steep.  “Early on, I was standing there in the hot sun watching Kim and our vineyard consultant go around making auger holes, pulling up dirt and squeezing the samples by hand to determine soil moisture.  We knew there had to be a better way.”

Their quest led them to partner with a privately-held Colorado firm, niolabs, a pioneer of distributed- edge computing software that specializes in large scale monitoring of just about everything and then using artificial intelligence to make precision operating decisions.  They turned their land into a digital vineyard.

Thousands of sensors

“Eighty percent of the wine is made in the field,” says Kim.  “Great wines begin with great fruit and great fruit requires a lot of attention to detail to produce high quality grapes and with thousands of sensors now embedded in the vineyard reporting the status of the soil, plant health, and the environment via software, “Our vines actually talk to us.  We know when they’re drinking, we know when they’re stressed or thirsty, because we’re constantly monitoring conditions.” 

So closely that data measurements are taken every 6 minutes at soil depths of 4”, 8”, 16” and deeper.  “We can literally watch the percentages change as plants take up water,” says Phil.  “Different pieces of information give you knowledge that can cause action and ultimately to strategic insight which is kind of like the holy grail for me to plan a strategic outcome to occur.  We don’t have to guess anymore.

“And we now have a complete history of 2018, our third grow year, so that in 2019 we know exactly what happened during the last entire year.  We have minimum and maximum soil moisture readings for every depth in every one of our 12 grow zones and can use that data in all our strategic thinking for 2019.”

Deep Sky and niolabs proprietary precision agriculture allows precise water delivery to each irrigation zone with instant updates of moisture and temperature at 6 different depths; measures vine root uptake of moisture at each depth to determine when and where to irrigate; evaluates vine stress based on amount of available water, and measures temperature and humidity differences to evaluate canopy effectiveness.

It’s like a lens into an underground world where voyeurs can watch as water is delivered and consumed by the vines.  And that close monitoring pays off in several ways.  First, “We’ve developed irrigation and chemical application algorithms where we only irrigate to the depth that the vines are taking in water.   In our third digital season, we saved over a million gallons,” he says.

Strategic insights

“We’ve seen some strategic insights into things like quality because we’ve reduced our berry size by 15-20% and dropped our crop load from 60 tons to 50 tons.  With smaller berries, as you shrink them, you increase the ratio of skin to juice and the skin is where the flavor is, particularly in red wine where you get a more robust flavor.  We’re getting our vines to do what we want them to do.

“Our fruit health has improved.  Initially we had a terrible time with bunch rot, but we dropped that by 30% in our 2017 Grenache and down to zero in 2018.  Bunch rot is caused by rain on football size grape clusters.  They rot from the inside out.  But now, with smaller berries, we’ve minimized the disease chances.

“ Our resource consumption is going down, especially water consumption that has dropped by roughly  100,000 gallons an acre because of more precise watering algorithms.

“Growing grapes in Arizona is kind of like wandering into the unknown because nobody really knows exactly how to do it.  In so many ways, we’re exploring how to grow grapes in an arid environment.”

Lovers of fine grappa are reminded that the 10^th annual Arizona Wine Growers Association’s Grand Festival takes place on January 27 in Phoenix.  Winners of the Arizona Wine Competition will be announced while more than 30 wineries from throughout the state will pour over 200 wines.

“This is AWGA’s largest event of the year, a wonderful opportunity to share the story and evolution of the state’s wine industry,” says Brian Predmore, former AWGA president.