New to the University of Minnesota's St. Paul campus, graduate student Emily Hoover watched Jane McKinnon swing into action on a campus "cleanup day" in the late 1970s.

Wearing a blue suit with a skirt and a frilly white blouse, "Miss Jane," as she was known, donned gardening gloves and rubber boots and began energetically pruning crabapple trees.

"She was a marvelous individual," said Hoover, now the head of the U's Department of Horticultural Science. "She was a wonderful southern woman who had an iron fist enclosed in a silk glove, very persuasive ... and kind and sweet."

McKinnon, who spent more than 40 years in Minnesota and never lost her Mississippi accent, died last month in Texas. She was 91.

Principled and proper -- she rarely wore slacks -- charismatic and warm, McKinnon helped educate a generation of horticulturists. She was key to the founding of Minnesota's Master Gardener program, which began with 25 people in 1977 and now has nearly 2,300 volunteers. She designed landscapes on the St. Paul campus. And as far back as 1965, she was telling Minnesotans that they needed to use more native plants.

She also dispensed gardening advice on the radio and visited every corner of Minnesota.

"She was so gracious and easy to get along with," said Mike Zins, retired extension educator. "People just loved her."

McKinnon's father was an agriculture extension agent who taught her about seeds and soil, she told the Star Tribune in 1987. She joined the Red Cross in World War II and met her future husband, St. Paul native Walter McKinnon, in India. They married in 1946, settled in White Bear Lake and had a daughter, Sarah.

McKinnon's first Minnesota garden was a disaster. Determined to learn more, she took classes at the U, earning bachelor's and master's degrees in horticulture. She joined the Extension Service in 1970 and was a full professor when she retired in 1989.

Deb Brown, retired extension educator, called McKinnon a mentor, a friend and a "wonderful, wonderful woman."

"She was always very sweet and polite but, boy, she got things done," Brown said. "She knew county agents from one end of the state to the other and was a favorite of everybody."

The St. Paul campus was still known as the "farm campus," with a mostly male faculty. McKinnon led the horticulture department for a while and became a mentor for younger female faculty. Remarkably unselfish, she gave credit for joint projects to students and other faculty and advised Brown to start a "brag file" to keep a record of the accomplishments she'd need to advance at the U.

"She said the men all do it," Brown said. "I never would have known this."

In 1989, McKinnon retired to Waveland, Miss., to garden "24/7, 12 months a year," her daughter said. Walter McKinnon died the next year. His widow filled her yard with flowering trees and a bog garden with native plants and the house with rescued cats and dogs.

Hurricane Katrina flooded the house with 4 feet of water and the flood tore the gardens away, but McKinnon was determined to rebuild. At age 85, she did.

"It gave her the inspiration to keep going," Sarah McKinnon said.

Besides her daughter, of Toronto, survivors include sisters Virginia Covington and Evelyn McCready. A memorial service will be held next spring in Mississippi.

Mary Jane Smetanka • 612-673-7380 Twitter: @smetan