Climate conditions ripe for more grape-growing regions in Colorado, CSU study says
Climate conditions that grow grapes in Palisade exist elsewhere in Colorado, which could expand the state’s wine industry, Colorado State University atmospheric and agricultural scientists say.
These areas exhibit similar traits that could allow more cold-hardy grapes to grow at scale, according to a new study led by Peter Goble, a climatologist and water availability specialist based in CSU’s nationally known Department of Atmospheric Science.
Goble conducted the study with Horst Caspari, a viticulture professor at CSU’s Western Colorado Research Center, and State Climatologist Russ Schumacher, who is also based at CSU.
Through climate mapping for the entire state, the team discovered particular areas could be ripe for grapes that more readily adapt to temperature changes: Montezuma County in the Four Corners, western Montrose County (home to Nucla and Naturita), Fremont County (home of Cañon City), and to a lesser extent, the Arkansas River Valley.
A few wineries already call those regions home, but the potential exists to expand an industry that already struggles with a “feast or famine” reputation, Caspari said.
“More vineyards, more production is a long-time goal for the Colorado wine industry,” he said.
The research, funded in part by the Colorado Wine Industry Development Board, appears in a recent issue of the Journal of Applied and Service Climatology.
The team studied Western Slope historical temperatures, accounting for complex factors such as elevation, slope gradient and direction. Those factors influence “microclimates” common across western Colorado that make it difficult to accurately apply temperature and climate changes universally.
The researchers measured real-time observations from temperature-monitoring networks and against data generated by a climate model. These data show where there is already potential for more viticultural activity in today’s climate.
Further research with climate models that make future projections is planned to see how things may change between now and the middle of the century, Goble said.
“We’re going to understand this even better a year from now,” Goble said. “We know that the terrain in western Colorado is incredibly complex, and that’s conducive to microclimates that may make it difficult to assess scale. While we do see significant warming trends over the last 50 years in Colorado, we don’t see as strong of trends in low-temperature injury events, or the kind of weather we’d expect to harm wine grapes.”
“The most exciting take is that there are other portions of the state with a climate similar to the well-known Grand Junction/Palisade area to be hospitable to this kind of agricultural operation,” Goble added, noting that it’s still too early to make definitive judgments about where these opportunities might be.
SMALL SCALE EXPERIMENTS
Interested wine growers in these areas might be willing to experiment on very small scales, he said.
“I would recommend anyone considering doing this get temperature measurements on their property because of these microclimates,” Goble said.
The big “uh-oh” factor for grapes is low temperatures before grape vines have had the chance to acclimate to winter weather. Those temperatures occasionally upend the viticulture industry in western Colorado – for example in 2009, 2013 and 2020.
The slightest temperature difference can impact plants. Even conditions within the Grand Valley — between Palisade and the Redlands near the Colorado National Monument — vary wildly, making it tough to grow cold-tender grapes, Caspari said.
On a tiny scale, there might be opportunities along the Front Range as well, but eastern Colorado experiences more intense cold air outbreaks during winter that could harm grapes, according to the study.
“It takes less than one hour of severe cold temperature to kill a plant to the ground,” Caspari said. “We get a killing frost but then we get mild temperatures again, which slows the plant’s cold acclimation. Then, when there is a sudden sharp drop in temperature, it’s too cold for what the plant can handle. We’ve seen a lot more damage in the fall in the last 20 years than we ever had. The temperature swing is getting bigger.”
The lack of cold hardiness of these plants and the resulting damage also means there has been no net growth in the wine industry in western Colorado over the past seven to eight years, Caspari said.