The wine industry’s battle with climate change

Vineyards deal with drought, temperature swings and fruit that ripens too early.

 

Winery owner Brent Helleckson’s hands flew among his budding grapevines, pruning off bits of cane as a spring breeze ruffled the plastic tape keeping the vines trellised to wires. Cut spurs, their ends as green as the grassy aisles between rows, glistened with sap flowing to the buds that had survived the winter. On the other side of Western Colorado’s North Fork Valley, snow lingered on mountain peaks, a reminder of the wintery weather that circumscribes the vineyard’s operations. “In theory we’re done with frost now,” Helleckson said. “But I wouldn’t bet on it.”

In a warming West, areas where wine grapes are growing at the limit of their cold tolerance may see a respite from frigid, plant-damaging winters. But other changes, including droughts, erratic swings in temperature, and earlier ripening may make viticulture more difficult even in cooler locations like Western Colorado. Warmer areas, meanwhile, including parts of California, may become too hot for the high-quality wine grapes that thrived there in the past. Thanks to the resilient nature of grapevines and the growing demand for regional wine, experts don’t expect vineyards to disappear from the West. However, which varieties are grown where, and at what cost, will likely continue to shift in the coming decades.

Viticulturists in Western Colorado must contend with winter temperatures cold enough to damage grapevines. While a warmer climate may ease that risk, problems like drought and erratic swings in weather may get worse in the coming decades.
Brooke Warren

Here in the North Fork Valley, cold temperatures, high elevation and volcanic and calcium-based soils result in “nicely acidic wine with lots of intense fruit flavors,” says Helleckson, who produces merlot, chardonnay, gewürztraminer and other wines at Stone Cottage Cellars. But that cooler climate carries risks: winter temperatures below zero degrees Fahrenheit can freeze vine trunks, forcing them to regrow from the roots, which takes years. In the fall, sudden temperature drops — the sort of variability that is expected to increase with climate change — can be particularly damaging if plants haven’t yet acclimated to colder weather. Vines desiccate slightly to allow internal water to freeze without bursting cells, for example, and the plants pump carbohydrates down to their roots, stockpiling energy to fuel spring growth.

The start of spring has been advancing across the United States; Helleckson has noticed early warm spells at his vineyard too. That can pull vines out of winter dormancy before the threat of frost is past, leaving buds susceptible to freezing. While cherries, peaches and other trees won’t fruit at all if a spring frost kills their blossoms, grapes get a second chance. A single freeze can kill the primary shoot within the bud but leave behind a secondary shoot, which yields about half the normal crop. That’s better than nothing, says Horst Caspari, Colorado’s state viticulturist and a professor at Colorado State University’s Western Colorado Research Center in Grand Junction, but growing grapes is, after all, a business: “We do want the full crop. We don’t want to be cropping on secondaries.”  

Warmer springs also mean the mountain snowpack melts more quickly. That can send runoff downstream before grapevines need it most, just after they’ve leafed out. If the timing is off, growers might need to start drawing on stored water for irrigation earlier than they typically would. “Once you start pulling out of the reservoirs,” Helleckson says, “there’s only so many days of water in there, and then you’re done.”

Brent Helleckson prunes grapevines in preparation for summer growth at his vineyard, Stone Cottage Cellars, in Paonia, Colorado. Growing buds closest to the tip of the cane secrete a chemical that impedes development of buds closer to the trunk, a process Helleckson exploits to keep buds from breaking too early, when there’s still a risk of a spring frost.
Brooke Warren

Drought and heat waves are already a problem for vineyards in other parts of the West, including parts of California, according to viticulture professor Markus Keller at Washington State University in Prosser. Although wine grapes are relatively drought-tolerant and they will still grow in hot, dry places, their quality can suffer, a prospect that could have major economic impacts: In 2015, California produced more than 80 percent of the wine made in the U.S. and the state’s wine grape crop was valued at $2.5 billion.

The quality of wine grapes is also affected by shifts in ripening times. In the last two years, wine grape growers in the Western U.S. have harvested their crops a month to six weeks earlier than what was typical a quarter of a century ago, says Gregory Jones, a wine climatologist at Southern Oregon University in Ashland. That change affects both the character of the fruit and the flavor of the wine it produces: It’s common to end up with less acidic grapes that have a higher sugar concentration, which can result in higher alcohol content. Winemakers can manipulate those qualities during production, but it’s unknown how artificial additions and subtractions affect the nature of wine, Jones says.

To keep producing top-notch grapes, viticulturists may need to relocate their operations. In California and Washington, for example, some growers are already planting vineyards further north or moving up in elevation, Keller says. They can also combat the heat by hanging shade cloth or positioning rows on a sun-sheltered north-facing slope. Another option is to grow varieties that are better suited to a warmer or drier climate, though that can become a moving target as the climate continues to change.

Growers may also have to cope with a shifting suite of insects and ailments. While moisture-loving pests like fungi or mildew may decline in areas that become warmer and drier, other bugs and diseases will likely take their place.

At Stone Cottage Cellars, Helleckson is planning to grow grapevines planted on grafted rootstock at a cost of several thousand dollars per acre to avoid the ravages of an aphid-like insect called phylloxera, first discovered in Colorado in late 2016. Phylloxera — which sucks sap from the roots of certain grapevine species while injecting a plant toxin, eventually killing the vine — probably didn’t get a foothold in Colorado because of climate change, says entomologist Bob Hammon, an agricultural extension agent with Colorado State University who is based in Grand Junction. But how growers protect their vineyards from the pest could offer a blueprint for handling future challenges. “Is the Colorado wine industry going to crash?” Hammon asks. “No, it’s going to adapt.” That will be true of the West’s wine industry overall as growers and producers face the realities of climate change.

Emily Benson is an editorial intern at High Country News.

High Country News Classifieds
  • SPORTING COMMUNICATIONS COORDINATOR
    To advance our mission, we are seeking a full-time Sporting Communications Coordinator to join our team, preferably in Montana or Colorado. (Due to COVID-19 all...
  • THE LAND DESK: A PUBLIC LANDS NEWSLETTER
    Western lands and communities--in context--delivered to your inbox 3x/week. From award-winning journalist and HCN contributor, Jonathan P. Thompson. $6/month; $60/year.
  • CONSERVATIONIST? IRRIGABLE LAND?
    Stellar seed-saving NGO is available to serious partner. Package must include financial support. Details: http://seeds.ojaidigital.net.
  • EXPERT LAND STEWART
    Available for site conservator, property manager. View resume at http://skills.ojadigital.net.
  • ANCESTRAL LANDS ADMINISTRATIVE MANAGER
    Starting Salary: Grade C, $19.00 to 24.00 per/hour Location: Albuquerque or Gallup, NM Status: Full-Time, Non-Exempt Benefit Eligible: Full Benefits Eligible per Personnel Policies Program...
  • GRAND CANYON DIRECTOR
    The Grand Canyon director, with the Grand Canyon manager, conservation director, and other staff, envisions, prioritizes, and implements strategies for the Grand Canyon Trust's work...
  • ADMINISTRATIVE ASSISTANT
    Great Old Broads for Wilderness seeks a part-time Administrative Assistant to support the organization's general operations. This includes phone and email communications, office correspondence and...
  • HISTORIC LODGE AND RESTAURANT - FULLY EQUIPPED
    Built in 1901, The Crazy Mountain Inn has 11 guest rooms in a town-center building on 7 city lots (.58 acres). The inn and restaurant...
  • ONE WILL: THREE WIVES
    by Edith Tarbescu. "One Will: Three Wives" is packed with a large array of interesting suspects, all of whom could be a murderer ... a...
  • PROGRAM DIRECTOR, SALAZAR CENTER FOR NORTH AMERICAN CONSERVATION
    The Program Director will oversee the programmatic initiatives of The Salazar Center, working closely with the Center's Director and staff to engage the world's leading...
  • WILDEARTH GUARDIANS - WILD PLACES PROGRAM DIRECTOR
    Salary Range: $70,000-$80,000. Location: Denver, CO, Portland, OR, Seattle, WA, Missoula, MT or potentially elsewhere for the right person. Application Review: on a rolling basis....
  • RIVER EDUCATOR/GUIDE + TRIP LEADER
    Position Description: Full-time seasonal positions (mid-March through October) Organizational Background: Colorado Canyons Association (CCA) is a 10 year old nonprofit organization fostering community stewardship of...
  • BOOKKEEPER/ADMINISTRATIVE ASSISTANT
    Position Description: Part-time, year-round bookkeeping and administration position (12 - 16 hours/week) $16 - $18/hour DOE Organizational Background: Colorado Canyons Association (CCA) is a 10...
  • LAND STEWARD
    San Isabel Land Protection Trust seeks a full-time Land Steward to manage and oversee its conservation easement monitoring and stewardship program for 42,437 acres in...
  • EXECUTIVE DIRECTOR
    Ventana Wilderness Alliance is seeking an experienced forward-facing public land conservation leader to serve as its Executive Director. The mission of the Ventana Wilderness Alliance...
  • COMMUNICATIONS AND DEVELOPMENT DIRECTOR
    The Quivira Coalition (www.quiviracoaltion.org) is a Santa Fe-based nonprofit that builds resilience on arid working lands. We foster ecological, economic, and social health through education,...
  • GRANT WRITER
    "We all love this place we call Montana. We believe that land and water and air are not ours to despoil, but ours to steward...
  • DEVELOPMENT DIRECTOR
    The Development Director is responsible for organizing and launching a coherent set of development activities to build support for the Natural History Institute's programs and...
  • WILDLIFE PROJECT COORDINATOR
    Founded in 1936, the National Wildlife Federation (NWF or Federation) is America's largest and most trusted grassroots conservation organization with 53 state/territorial affiliates and more...
  • EXECUTIVE DIRECTOR
    The Cinnabar Foundation helps protect and conserve water, wildlife and wild lands in Montana and the Greater Yellowstone Ecosystem by supporting organizations and people who...