Mary Louise Seilheimer

Mary Louise “Mary Lou” Morton Seilheimer, of Orange, Virginia, a devoted wife, mother, grandmother, gardener, philanthropist, and community leader, died peacefully at her beloved home, Mount Sharon, on July 26, 2026, surrounded by her family. She will be missed not only by her family and friends, but also by the institutions and causes to which she donated generously of her time, talents, and treasure.

Mary Lou was born on June 6, 1941, in Washington, D.C., to Anne Morton (a native of Columbus, Georgia) and Jack Morton (originally from Wilson, North Carolina), founder of Jack Morton Worldwide, a leading global experiential marketing firm. She graduated from Mount Vernon Seminary in Washington before graduating cum laude and Phi Beta Kappa from Sweet Briar College. She worked as personal and social secretary to the Ambassador of Finland to the United States before serving as Alumnae Director of Mount Vernon College.

In 1966, she married Charles H. Seilheimer Jr., who would go on to become founder, President, and CEO of Sotheby’s International Realty Corporation. Together they moved to Warrenton and purchased Leeton Forest, an architecturally distinguished house where she created a beautiful home for her family and all who visited. She focused on raising her children and serving her community. Mary Lou joined the Board of Trustees of Highland School before serving as Chairman for more than a decade.

During this time, gardening became both Mary Lou's greatest passion and one of her life's defining legacies. Inspired by a love of horticulture inherited from her father, she developed an extraordinary knowledge of plants, landscape design, and historic gardens. She found her deepest happiness outdoors, creating and tending to the gardens she loved.

 She joined the Warrenton Garden Club, one of the few clubs to be a founding member of both the Garden Club of America and the Garden Club of Virginia, served as its President, and remained an active member for over fifty years. She also served as Chairman of the Garden Club of Virginia’s Restoration Committee, overseeing the stewardship of forty-seven of Virginia’s most historic gardens. In recognition of her many contributions, she received the Garden Club of America's Zone Historic Preservation Award and the Garden Club of Virginia's Massey Medal, its highest honor.

In 1995, Mary Lou and Charlie moved to historic Mount Sharon with a vision of creating extensive and varied gardens, inspired by the Italian, French, and English landscapes they studied during their travels abroad. Mary Lou poured her heart into the gardens and found joy in the time she spent planting, weeding, pruning, and sharing the fruits of her labor with others. Featured in numerous publications, the gardens have come to be recognized among Virginia's most admired private gardens. The Seilheimers have welcomed countless garden clubs, horticultural groups, and friends to Mount Sharon, while also hosting events to raise funds for their favorite charities.

Mary Lou’s desire to support young people in her community led her to become deeply involved with the Boys and Girls Club of Orange. She worked tirelessly to advocate for the organization, eventually serving as its President while also serving on the Board of Directors of Boys & Girls Clubs of Central Virginia. The Boys & Girls Clubs of America honored Mary Lou with its highest distinction, the National Medallion, for her “exceptionally devoted and exemplary service.” Her leadership was marked not by a desire for recognition, but by quiet wisdom, kindness, and the ability to bring people together in common purpose.

A deeply spiritual person, she served on the vestries of both St. James Church in Warrenton and St. Thomas Church in Orange. She is survived by her husband of 59 years, Charlie; her daughter, Anne (Josh) Prentice; her son, Charles (Nora) Seilheimer; her grandchildren, Julian and Louisa Prentice and Henry and Parthie Seilheimer; her sister, Diane Morton Fentress (Lee); her brother, William Morton (Kay); numerous nieces and nephews; and Millie, her devoted Labrador retriever.

A service celebrating Mary Lou’s life will be held later this fall at St. Thomas Episcopal Church in Orange. Burial will be private. Memorial contributions may be made to the Mary Lou Seilheimer Building Great Futures for Orange Endowment at the Boys & Girls Club of Orange.

Mary Lou leaves flourishing gardens, enduring institutions, and, above all, a legacy of hospitality, faith, generosity, and love that will continue to bloom in the lives of all who knew her.