Photos by Katie Noble

When the bare and bone-chilling cold stretch of a New England winter sets in, the bright flavors of ripe Valencia oranges and fresh berries that Bonnie Shershow grew up with on her family’s California fruit orchard can feel like distant memories. “I came here when my children were little and at first I was thrilled to be on the East Coast,” she says. “It was like being in a movie with subways and snow, but soon I realized how long the winter was, and how cold.” Many years later, one of her favorite ways to fight off the chill is to open a jar of jam she made at the height of summer. “It takes me back to my childhood,” Shershow says. “There’s a link there that feels wonderful.”

Shershow’s burgeoning company, Bonnie’s Jams, was born in her cozy kitchen in Cambridge in 1999. “We had a plum tree and a grape arbor and I always made jam when it was the season to make jam. But then I started making it when I needed to think,” she says. “It’s Zen-like for me, taking unruly fruit, turning it into something really beautiful and putting my label on it.” Shershow perfected her recipes at home in copper pans, making jam in small, slow-simmered batches so it thickened naturally without added pectin. She also used less than half the sugar of some traditional jam recipes to showcase the true flavor of the fruit.

In her first commercial foray she took her jams to Formaggio Kitchen, whose owners agreed to sell them and to let Shershow make more on site. Soon a customer suggested that Bonnie’s Jams would be a hit in New York City. “One of my first sales outside the local community was to Eli Zabar’s,” Shershow says. “I was still doing other things but that was the first trigger. I thought I could make a business out of it.”

Starting the company was a major shift from her work in the non-profit world. Shershow has a degree in public policy from Harvard’s Kennedy School and worked as an aide to Kitty Dukakis during her husband’s 1989 presidential bid, as well as on the campaigns of Barney Frank and Ed Markey. “Now I don’t have time for anything but the jam business,” she says. “It’s all encompassing.”

Shershow’s company soon outgrew the kitchen at Formaggio and she needed to scale up but wanted to do it without sacrificing quality. She spent more than three years searching for the right facility before she found one in Lynn where she could increase production under her supervision. She found distributors on the East Coast and this year she has added more in the Midwest and Northern California. Her jams are now sold in more than a dozen states, at independent local markets as well as national chains like Whole Foods and Williams-Sonoma.

As Bonnie’s Jams expanded, Shershow says, she also outgrew her ability to use mostly local ingredients. “New England has really good fruit but our growing season is so short that you can’t depend on it if you want to have a larger business.” She uses some berries from Massachusetts but also sources fruit from New Jersey, Michigan, Oregon, California, and other states.

She currently produces nine flavors, including Raspberry Lime Rickey, Strawberry Rhubarb, and her best seller, Black & Blue—a tart but sweet blend of blackberries, blueberries, and a touch of lemon that’s delicious when spread on buttered toast or simple crackers with fresh goat cheese. Shershow says her Peach Ginger and Apricot Orange jams also compliment savory dishes as a glaze for roast chicken, pork, or ribs. For those frigid mid-winter mornings she suggests spreading some jam on hot French toast or pancakes for a little taste of summer.

Bonnie’s Jams are available at Allandale Farm in Brookline, Formaggio Kitchen in Cambridge and the South End, Savenor’s Markets in Boston and Cambridge, and other retail locations. For the full list, visit bonniesjams.com.

This story appeared in the Winter 2014 issue.