Pueblo loves its green chiles. So much so that each September, the city invites some 140,000 capsaicin converts to its annual Chile and Frijoles Festival (September 24 to 26; $5). While local farmers have been growing peppers for more than a century, chances are the ones you’ll be enjoying at this year’s event can be traced back to one man: Michael Bartolo, a local son made good as an agricultural research scientist at Colorado State University’s Arkansas Valley Research Center. After years of work, Bartolo officially introduced the Mosco, a meatier version of Pueblo’s namesake chile, in 2005. More amenable to roasting, it soon became the region’s dominant variety and even beat out New Mexico’s famous Hatch pepper as the green chile of choice for Whole Foods Markets throughout the Mountain West. Now that Bartolo is retiring, we spoke with him about his quest to create the perfect pepper.

5280: You didn’t intend to develop a new kind of pepper. How’d it happen?
Michael Bartolo: When I returned to Colorado in the early ’90s after earning my doctorate in plant physiology at the University of Minnesota Twin Cities, I inherited a bag of seeds from my uncle, Harry Mosco. He was a farmer, and he’d passed away a few years before. I planted them, and it was sheer luck that I was walking along one day and said, “Jeez, that’s an interesting pepper. I think I’ll take the seed for next year.” After another eight to 10 years of selections, I finally had a stable variety.

You’ve since created three more unique varieties. What does it take to bring a pepper to market?
I don’t know if there is an ounce of skill involved in what I do. It’s trial and error, with a lot more error. I find a plant with unique traits, isolate it, and try to grow it year after year. Sometimes those desirable traits [thicker walls, a spicier flavor, or an interesting shape] reappear in the next generation, and sometimes they don’t. Hopefully, you eventually get something that produces a consistent crop, but a lot of times things just don’t work out.

Is the rivalry between Colorado and New Mexico chile farmers real?
It’s kind of like professional wrestling. Hulk Hogan and Andre the Giant would go after each other in the ring, and then backstage they’d be best friends. I think chile growers on both sides of the border appreciate each other. They know how hard it is to be a farmer, so anything that helps raise awareness is a good thing.

What’s retirement going to look like?
I’ll have my hands in the soil somewhere, messing with chiles, but I also want to be an advocate for agriculture. If we develop a better relationship with it, maybe it won’t go away in the wake of the unbridled growth we’re experiencing in this state. It’s already happening in Pueblo. Some of our richest chile-producing lands have been developed or had the water rights sold.

What’s your favorite part of harvest season?
I just love looking at the chiles. I’ll spend hours at the research farm crawling through the rows of pepper plants on my hands and knees. I’m obsessed with finding the next interesting pepper. I know there’s one out there, and I just keep looking and looking.

What’s the best way to enjoy a Pueblo chile?
The simpler the better—just a roasted chile and a tortilla or piece of Italian bread. There’s something reassuring about that. Hopefully, that’s what St. Peter will be handing out at the Pearly Gates.

This article was originally published in 5280 September 2021.
Nicholas Hunt
Nicholas Hunt
Nicholas writes and edits the Compass, Adventure, and Culture sections of 5280 and writes for 5280.com.