John F. Gardiner III, who retired as president of Potomac Basin Group Associates, died Wednesday of complications from hyponatremia, a blood disorder, at his Severna Park home. He was 63.
The son of John F. Gardiner Jr., a Foreign Service officer, and Maria Louisa Briscoe Gardiner, a homemaker, John Francis Gardiner III was born in Washington, and because of his father's career, was raised in Tokyo, Munich and Potomac.
After graduating in 1970 from Winston Churchill High School in Potomac, he attended Mount St. Mary's College in Emmitsburg.
Mr. Gardiner was working as manager of Lakewood Country Club in Rockville in 1983, when he took a job at Potomac Basin Group Associates, also known as PBGA.
In 1997, he was named president of the Beltsville insurance brokerage, which is one of the top 10 brokerages in the Washington metropolitan area. He retained that position until retiring last year.
A gardener, he particularly liked caring for his azaleas and his bonsai collection. He enjoyed attending Southern Maryland oyster and crab feasts.
Mr. Gardiner was an Orioles, Ravens, Nationals and Redskins fan. He liked vacationing at the Delaware beaches and at the Outer Banks of North Carolina and Jupiter, Fla.
He was a member of the Southern Maryland Society, Annapolis Yacht Club, Chartwell Country Club and Friends of Sotterley Plantation, his mother's family's ancestral home.
Mr. Gardiner was a communicant of Our Lady of the Fields Roman Catholic Church, 1070 Cecil Ave., Millersville, where a Mass of Christian burial will be offered at 11 a.m. Tuesday.
Mr. Gardiner is survived by his wife of 29 years, the former Valerie Avedon; a son, John F. Gardiner IV of Severna Park; a daughter, Laura Gardiner of Jupiter, Fla.; his father, who lives in Leonardtown; two brothers, Walter Gardiner of Vienna, Va., and Joseph Gardiner of La Plata; two sisters, Maria Steppe and Marian Fegeley, both of Hollywood, St. Mary's County; and eight nieces and nephews.