An Unlikely Success Story
By Stacy Carlson
Sweet, juicy peaches grow best in regions where a Mediterranean climate provides hot, dry summers followed by mild winters that rarely freeze. Most of China, where 65% of the world’s peaches come from, meets these criteria, as do the next largest peach producers: Italy, Turkey, Greece and Spain. In the US, California’s San Joaquin Valley (another Mediterranean climate) pumps out 475,000 tons per year, about 75% of the country’s total peaches.
These growing conditions have little in common with Minnesota’s humid summers, frigid winters and “whiplash” spring weather that can bring 50-degree temperature drops in 24 hours and wreak havoc on early blossoms. Logically, it follows that growing peaches would be a fruitless endeavor (literally). But it turns out our state is home to someone whose insatiable appetite for experimentation has worked stone fruit magic to produce 1,500 pounds of peaches per year from a small farm in Taylors Falls. Meet Dan Sheild, Minnesota peach whisperer.
“If someone gave me a million dollars and six helpers, I’d have a thousand ideas of what to try,” Dan says. “I am constantly thinking about variations and asking, what happens if I do this? Why did the trees do that, and what can I do differently next time?” This spirit of curiosity and humble audacity infuses Dan’s approach, which has resulted in a unique growing setup. His 30-acre farm is home to 60 varieties of organically grown peach trees, but not in a conventional orchard. The trees flourish inside three high tunnels — 74 feet long by 34 feet wide greenhouse structures with high, rounded roofs. These tunnels provide some of the components missing from the Minnesota climate: temperature regulation and protection from blossom-destroying wind. Dan’s inventiveness provides the rest.
“This whole experiment started with a question that’s actually quite philosophical if you think about it,” Dan recounts. “Why is darkness important?”
Rewind to 2010, four years before Dan moved to the farm. At the time, he lived in Bloomington and considered himself an average backyard gardener. Out of curiosity, he decided to grow a smooth-skinned peach variety: the Flavortop nectarine. “This nectarine is known to be very sensitive to the cold,” Dan shares with a characteristic gleam in his eye. “I thought, if I can grow this on my property, then I know I can do anything, right?” Dan trellised the nectarine to the south side of his garage, and to protect it during winter, he placed a 10 feet by two feet plywood box over it. He also stuck a small Honeycrisp apple tree inside to protect it from rabbits. “When I took off the box in April, the peach branches were still lime green. The previous year’s leaves were still on the apple tree, and they were still healthy, still looked like they did the day I covered it. I asked myself, what just happened?”
Turns out, Dan had essentially frozen the trees in time. Without the gradual decline of daylight hours that nature provides, the trees didn’t go through the step-by-step process of dormancy. Instead, they stayed in a state of suspended animation, persevering with leaves intact through zero-degree weather. “Light is the effector,” Dan explains. “Through this experiment I learned the power of the absence of light on a plant. I always thought light was beneficial, and everyone told me I needed to have the trees exposed to light all year round. But I had data and experience that showed otherwise.”
Inspired by this early experiment, and fueled by the love of a challenge, Dan’s tinkering and curiosity only grew. Over the next decade, he built a peach-growing system that not only overcomes the climatic obstacles of our region but also produces peaches many have described as the best they’ve ever tasted.
Inside the high tunnels, Dan started with meticulous soil preparation, low-cost irrigation systems and a wide variety of peach cultivars. He prunes the trees to about seven feet tall by five feet wide so he can easily harvest by hand. Building on his initial experiment in Bloomington, Dan’s methods for controlling light exposure also have scaled up and are the key to the system’s success.
Thick silage tarps, white on one side and black on the other, force dormancy in winter and help provide as close to ideal conditions as possible during the growing season. From roughly April to November, the tarps are off the high tunnel roofs but play an important role inside. “We lose approximately 15% of the sunlight as it passes through the high tunnels’ clear plastic roofs,” Dan says. “So we lay down the tarps white side up on the ground inside the tunnels, where they reflect light back up into the trees.” Dan describes getting sunburnt on the underside of his chin the first year he tried this method, so he knows it works.
Between November and March, Dan covers the tunnels with the tarps, black side down, leaving the trees in almost complete darkness. In addition to forcing dormancy, this practice has other important benefits. “I’ve learned that the most important reason to block winter light is to prevent heat spikes,” Dan shares. “On a 30-degree winter day, it could be 60 degrees in the high tunnels. I can’t have that. The tarps insulate the peaches, so they stay in an optimal temperature range.”
Come spring, Dan waits to remove the tarps until conditions are right for peach blossoms. He can keep the buds at “white tip” — almost ready to burst open — for weeks if he needs to, until the risk of frost and high winds is past. Once the tarps come off, the trees burst into bloom, and Dan does whatever he can to support successful pollination. Since peaches can be wind pollinated, the system isn’t dependent on bees getting into the tunnels – though Dan certainly hopes they will visit his fruit trees, as he has noticed how fruit pollinated by insects is shaped better. To ensure pollination throughout in case there aren’t enough insects to get the job done, Dan shakes the trees and sets up a fan so the pollen gets where it needs to go.
The high tunnel system works better than Dan ever imagined. He finds his peaches are sweeter than average, since the trees aren’t diverting nutrients and energy to recover from wind damage or fungal diseases; their resources go straight into the fruit. Overall, the trees also have been more productive than he expected. “I have a Blushing Star peach tree that produced 50 pounds of delicious fruit the first year it was viable. The second year, I had 88 pounds. The third year? 90 pounds. Those were all years I thinned the tree. When I didn’t thin it, I had 120 pounds of peaches!”
After twelve years working on the system, Dan still describes it as experimental, with fluctuating production due to trial-and-error. But he estimates that with all three high tunnels at maximum production, the farm could produce 4,500 pounds of peaches annually. “With the gradual warming of our climate, peach-growing regions are inching north. All of this will be relevant for others growing stone fruit. Plus, right now the peaches we find in Minnesota grocery stores travel 2,000 miles to get here. If we can erase that carbon footprint, all the better.” Reducing environmental impacts is just one reason to support locally grown food and emerging Minnesota crops, especially with current tariff uncertainties and federal funding cuts negatively affecting small farms across the state.
Supported by grants from the Environmental Quality Incentives Program (EQIP) in Chisago County, North Central Sustainable Agriculture Research and Education (SARE) and Minnesota Department of Agriculture, Dan has been able to lean into the art and science of peach growing in the Upper Midwest. In the process, he’s become an informal mentor for others in the region, and he hopes his years of experimentation and data will eventually lead to more awareness of stone fruit cultivation in the region. “I’ve had folks from Duluth interested in growing peaches and I say bring it on. With the right varieties, I think the system would work in outside temperatures down to 40 below. We need somebody to try that!”
Today, most Minnesota farmers growing stone fruit cultivate small plum, cherry or apricot orchards for the niche u-pick market. But Dan hopes that one day his farm will become a learning and research center with enough resources (labor, mostly) to prove that Minnesota peaches can be commercially viable and profitable. “I really think that’s possible,” he says. “I’m seeing nothing but a bright future ahead for peach growing in the Upper Midwest.”
So after all this work, what are some of Dan’s favorite varieties? He’s got white and yellow peaches and even a gorgeous, red-fleshed French heirloom variety called the Pêche de Vigne (vineyard peach). As perennial favorites, he cites an early Red Haven variety with notes of vanilla, the Saturn donut peach and Winblo, a yellow peach known for its sweet, juicy and creamy texture.
Dan doesn’t sell his peaches at farmers markets and doesn’t have a website, instead he uses his Instagram account (@dan_sheild) to announce availability and communicate directly with customers. This lo-fi system works; people flock from all over the state and beyond to purchase his rare commodity. “I have someone who purchases all the peaches off a specific tree each year,” Dan shares. “Like apple or blueberry picking, I think it’s an annual tradition for people to come up here for peaches.”
Some even make a weekend getaway out of the trip, since Dan hosts campers on his farm via hipcamp.com (search for Stone Creek Farm, Taylors Falls). He offers four campsites, so anyone interested in seeing the growing system firsthand can do so. Dan recommends reserving a site between the first week of August and the end of September for a peach-filled experience.
Dan’s experimentation and perseverance defied the odds to produce an energy-efficient and sustainable, though still rare, local delicacy. It’s no wonder fresh Minnesota peaches taste so sweet.
Stacy Carlson is a novelist, naturalist, and home herbalist based in Minneapolis. She serves as education program manager for Women’s Environmental Institute, a grassroots nonprofit dedicated to organic farming and food justice. Her background also includes work as a historical ecologist, hot springs caretaker, biological field crew on a bird refuge in SE Alaska, and hiking guide in Big Sur.
