Colorado fruit growers are celebrated for producing some of the most delectable peaches and cherries in the world. Grown on the Western Slope, the state’s stone fruits are known for their sweetness thanks to sunny days, cool nights and a soil full of minerals.
Still, even if the days are sunny, the business can be tough. Growing fruit in Colorado has always meant contending with hail, snow in September and 100 degrees in August, said Kacey Kropp of First Fruits Organic Farms. His family has been farming in Paonia for 40 years: His grandfather started the farm with the idea it would be a good retirement gig. Farming turned out to be a lot of work, and Kacey’s dad and uncle joined the effort.
That’s even more true now, as climate change, fed by our thirst for fossil fuels, brings drought, stronger storms and even wilder temperature swings.
Spring was always a challenge for fruit growers: Those historically erratic temperature swings, when tree blooms are vulnerable to freezing, were around long before climate change.
“But climate change has resulted in greater weather variability and more freak weather events,” Kropp said. “This can look like abnormal warmth in winter and early spring that get fruit buds accelerating, only to be wiped out by spring frost events.”
A damaged fruit crop doesn’t crush Colorado’s economy. Coming in at around 5,000 acres, the fruit-producing region is relatively small. Of the $7.48 billion in Colorado farm cash receipts for 2019, fruit amounted to only a fraction of the state’s crops.
But there’s no doubt that fruit adds a little sugar, and character, to the state’s snack table. No fruit does this more than peaches.
According to Catherine Boxler, business development specialist at the Colorado Department of Agriculture, Charlie Talbott from Talbott Farms said this past year’s peach crop was 26 million pounds, contributing about $30 million to the state’s economy.
Fruit is predominantly grown in Mesa, Delta and Montrose counties. Beginning with apple orchards in the 1870s, producers began focusing on peaches in the 30s.
Grapes also followed the wine-tasting craze, and at a range of 4,000 to 7,000 feet of elevation, count among the highest vineyards in the world. Today there are around 170 licensed wineries, as opposed to two in 1977. Talbott said the wine grape yield last year was 3,000-3,300 tons, adding $4.5 million to the state economy.
Farming was never going to be a sure thing, but Kropp, 28, can’t help but see a future in it, the same his father and grandfather saw, as long as the climate will allow it.
“The lifestyle is amazing but anxiety inducing,” he said.
Colorado’s historic weather challenges are becoming more erratic
For proof, Kropp points to last year’s polar vortex on Oct. 26, 2020, which saw the mercury plummet overnight from a balmy 60 degrees down to single digits in Palisade and Paonia. That early freeze destroyed cherry orchards and wiped out or damaged thousands of fruit trees. At First Fruits, Kropp said they took a chain saw to between 500-1,000 trees to prune off the damage.
Horst Caspari, a professor at Western Colorado Research Center-Orchard Mesa, grows wine grapes at one of the center’s three stations. He said that with the October 2020 event, based on records going back to 1895, temperatures went from the warmest 24 days on record to 14 degrees. Those vineyards lost 85 percent of the grape crop to the frost. While several cultivars survived, if you like Chardonnay, Merlot or Cabernet Sauvignon, Caspari said you’re out of luck.
Even though Colorado is a cold state, in his 21 years, Caspari has seen 12 frost events in the fall. An early spring frost has only happened once. Caspari said there were three times as many extreme events in the last 20 years based on 120 years of historical records.
Helping farmers understand how climate change affects crops
Peter Backlund, CSU Associate Director of the School of Global Environmental Sustainability, helped write a United States Department of Agriculture report, “Climate Indicators for Agriculture,” to help agricultural producers understand the threat and risks to their operations by measuring decades worth of data collected across the United States, Backlund said.
Identifying20 indicators was key to pinpoint issues affecting crops across the country. For Western Slope fruit growers, the primary factors at play are earlier bud break and bloom, the existence of microclimates, and extreme water shortages.
“It’s very seldom one thing, it’s a complex interplay of changing extreme conditions,” Backlund said. “The story is one of complexity and multiple changes playing off against each other affecting the fruit.”
Earlier bud break in fruit trees
The climate’s already changed enough to affect the growing season. Caspari and other researchers said the growing season has been extended by almost two weeks.
“Looking at data back to 1964, our last spring frost moved forward by roughly a week earlier, in fall moving back 5-6 days for the first fall frost,” Caspari said. “Growing season has been extended by 10-14 days. But we still have frost in May and early frost in October, when theoretically we shouldn’t have frost.”
It seems rational to think that longer growing seasons are beneficial because there could be potential for higher production, but with a longer season, what you’re experiencing are periods of greater risks, Backlund said.
Climate change creates greater fluctuations in the temperatures. Arthur DeGaetano, a co-author of the USDA report and a research climatologist and professor at Cornell University, said that fluctuations in the jet stream because of increased carbon dioxide levels are the culprit.
“The leading thinking in the United States is that the unusual spring or fall freeze events are from an excursion of the jet stream, which is effective at keeping the cold air over the Arctic and milder air over the middle regions of the country, which includes Colorado,” he said in an interview.
DeGaetano said to think of the jet stream acting as a strong fence. Because the Arctic warms faster than other parts of the planet now, it weakens the temperature gradient and the jet stream meanders more. The spread and variants in the stream’s wave sizes are what cause problems in fall and spring.
With warming, there is the potential for buds to be primed for development and bud break occurring as early as mid-February, whereas it used to be that the trees stayed dormant and didn’t bud until March. As we all know, there’s frost in February.
Even if the bloom and climate move in concert with each other, if it happens that trees bloom earlier and the whole temperature cycle moves in tandem, there’s little frost risk, he said.
But because the temperature swings are so wild, if there is a frost, the tree doesn’t have time to prepare. This is why early fall frosts are so damaging: A tree prepares for fall dormancy as temperatures cool, when a leaf disconnects from the branch.
“Its attachment point starts to harden,” said Brian Coppom, Executive Director of Boulder County Farmers Markets. “Once it does this, it starts to die and has chlorophyll loss, or the color change. The leaf has cut itself off from its nutrient source and then it falls off. With the rapid temperature swing, a tree doesn’t have time to prepare for the cold temperature, so the leaf won’t detach from the branch, leaving (the tree) vulnerable to freezing.”
David Sterle, Pomology Research Associate at the research center, said there are technological advancements with plant growth hormones to trigger earlier dormancy in the fall.
“The tree should be dropping leaves and entering fall hardiness, but it’s still proceeding like it’s summer,” he said. A topical Abscisic Acid spray is in the research stage and not available to farmers, but gets trees to turn yellow two weeks earlier, inducing dormancy to better prepare them for the early freeze event.
Other options historically have been reducing fall irrigation, Sterle said, but noted that the risk of frost and fall freezes goes beyond crop loss.
“You have significant wood damage making the tree more susceptible to disease,” Sterle said of the frost.
The problem with microclimates
One of the toughest challenges for Colorado fruit farmers are the existence of microclimates. Caspari said microclimates can exist within 200 feet in a vineyard, with temperature differences in the same field depending on whether there is a slope or not.
“Cold air moves like water on a calm night,” he said. “It’s heavier than warm air. It sinks to the bottom and pools.”
This also makes it harder for farmers to know what’s coming. Greg Litus, manager of the research center, said there are varying conditions between Palisade, which is the warmest, and then west into the North Fork Valley near Paonia and Hotchkiss, where temperatures are colder.
“One grower might make it through the season, but another a few miles away lost their entire crop. There is no one size fits all,” he said.
Fans, or wind machines, are common practice but only work in an inversion situation when it’s not too cold. If used, the fan pushes warm air down to replace the settling cold air.
Kropp said First Fruits uses propane heat in especially valuable but vulnerable blocks of fruit.
“It works. It’s expensive. And yes, it’s burning fuel to try to save fruit,” he wrote in an email, acknowledging the irony.
Water shortages more than anything are the problem
The western part of Colorado is experiencing what Backlund calls a ‘mega drought.’ “We’re in the 20th year of extremely limited rainfall and the whole system is starting to stress,” he said.
The recent emergency declaration for water cutoffs on the Colorado River by the federal government has a dramatic impact on central Arizona, Litus said. But Colorado is fairly stable and will be less impacted. Even so, in the North Fork Valley, smaller irrigation distribution systems coming off the Grand Mesa had water cut off on August 17.
“Those growers are at mercy of rain or a crop that can draw out moisture stored in the soil,” he said.
The reason is evapotranspiration: “The sum of evaporation from the land surface plus transpiration from plants,” Litus said, which has increased by 20% because of increased temperatures. That translates to having 20% less water.
Of the water in Western Slope irrigation systems, up to 90% goes to animal and forager crops like hay and alfalfa. Very little goes to fruit. But the water that’s distributed through federal irrigation districts is allocated based on acreage, and releases occur for growers with larger acreages. If releases are made in June or July for corn crops, fruit growers needing water later in the year are at a loss, Litus said. And with the shut off, now those growers are out of luck.
Paradoxically, climate change increases the amount of moisture in the atmosphere, Backlund said. You see that with more rainfall that, because of evapotranspiration and higher temperatures, dries the soil out faster. Colorado is also seeing increased snowfall, but with warming there is early runoff. This makes water management more complicated. There isn’t the gradual, historical release of the snowpack; instead hotter spring temperatures mean the runoff occurs earlier, all at once, instead of steadily flowing throughout the summer. Management varies between the big systems and smaller irrigation systems, creating another challenge.
“Diversion, storage, and distribution of water across western Colorado and the exceptional drought is affecting the distribution,” Litus said. “The impacts in Arizona will start to reach the Colorado River basin.”
Will fruit-growing remain economically viable in Colorado?
“The jury is still out on if we can remain economically viable growing fruit in Colorado’s different microclimates,” Sterle said. “That area might be shrinking. Right now there’s very little we can do to affect the hardiness of the trees to survive the large temperature swings.”
Caspari said grapes are drought-tolerant cultivars, using less than half the amount of water as peaches.
“Shifting away from especially frost-tender fruits like cherries may be best, but this means spending to uproot trees that should produce for decades,” Kropp said. “This is a tough puzzle to solve.”
Anecdotally, Litus has heard some growers will cut back on their acreage. The loss of young trees that happened because of the October vortex will require farmers to establish a new orchard. “It’s hard to do that without water. If you lose water in August, those trees will stress. The water is the most acute issue. If they can’t get water, they’ll start making decisions on orchard size.”
Scientists aren’t sanguine about the future, Backlund said, recognizing there are tools to address the challenges. More research on varietals that interplay with climate change is needed to provide the knowledge base for farmers so they can continue to adapt.
Kropp thinks that to preserve Colorado fruit down the road, they’ll see policy battles with water and a prioritization of farms with good stewardship of land and efficient water use.
If you love the taste of a Colorado peach, Kropp’s advice to keep Colorado growers going is simple: Show up and buy directly from the farmer, either through Consumer Supported Agriculture, farmers markets or farm stands.