Not many things can tolerate the negative 44 degrees Fahrenheit temperature of Grand Rapids, Minn. But surprisingly, some roses developed at the University can brave that cold better than most people.

Three new roses, developed by researchers in the University’s Department of Horticulture, can withstand those harsh climates and will be sold and planted for the first time this spring. The names of the roses – Sven, Ole and Lena – reflect Minnesota’s Norwegian influence and climate.

Sven has been the most popular among nurseries so far, according to former University plant breeder Kathy Zuzek. Sven is a violet color and Ole is light pink, Zuzek said. Lena is pink and white with about five petals, while Ole and Sven have many petals.

The process began in the early 1990s, Zuzek said. The plants that researchers were looking for had to be disease-resistant, have repeated blooming, an attractive appearance and hardiness.

The new strain took 11 years to create, but the lengthy process didn’t take away from the reward, Zuzek said.

“It’s been a project that I started and I grew,” she said. “So it’s thrilling when you have a final result.”

After propagating the new plants for about four years and evaluating them for winter-resistant traits, the three plants that made the cut were copied and sent to nurseries in Grand Rapids, Morris, UMore Park in Rosemount and the University nursery, each for another four years of testing.

These roses are tougher in cold conditions because of the plants’ genetics and the traits they inherit from their parent plants, Zuzek said.

“It’s really the plant’s ability to respond to shortening days and dropping temperatures,” she said. “It’s really the behavior of the plant in response to the environment it’s growing in.”

However, horticulture project scientist Steve McNamara said the genetics behind the roses aren’t explicitly defined yet.

“Nobody really knows which genes are accounting for that cold tolerance,” McNamara said. “You just try to pick the hardiest parents you can find and cross those.”

After the final product was finally chosen, it was copied by Bailey Nurseries, a wholesale nursery in Newport, Minn. Bailey gave the flowers their Norwegian names, Peggy Anne Montgomery, a Bailey Nurseries horticulturist, said.

“Lena, Sven and Ole very much say ‘Minnesota,’ which is a cold climate,” Montgomery said. “These roses aren’t going to be big sellers in Georgia.”

Bailey distributed all the roses to other nurseries and retailers early last summer, Montgomery said.

Linder’s Garden Center in St. Paul will sell the roses starting in May, Jim Stillings, who works in Linder’s nursery, said.

“We’re getting a lot of calls on them right now,” Stillings said.

Even some local personalities are interested in the University’s roses.

“Sven Sundgaard’s mom called the other day, and she wants some,” Montgomery said. “We’re going to make sure she gets them.”