Relatives and close friends said one last goodbye to the former first lady beneath a canopy of oak trees near the banks of the Pedernales River.
Grandson Lyndon Nugent said Johnson made each of her grandchildren feel special, whether she was taking them on hiking and camping trips or, especially in her later years, quietly visiting with them at the LBJ Ranch.
His mother, Luci Baines Johnson, reminded her children for more than three decades that it was important to spend as much time as possible with their grandmother, whom they called "Nini," because "she might not be here tomorrow," Nugent said.
"Sadly, tomorrow has arrived," he said.
Johnson died Wednesday at age 94 of natural causes. Through three days of memorial ceremonies, she has been remembered as the devoted wife of a president, an astute businesswoman and a tireless worker for the preservation of wildflowers and native plants.
"I'm not sure why she was so preoccupied with this, but she always seemed to be wondering if she had done enough for the world, regardless of her own condition," Nugent said.
Toward the end of her life, she gradually lost some of her vision and suffered a stroke that left her with difficulty speaking. But she still managed to enjoy the Texas wildflowers each spring and make some public appearances.
Locusts whistled and crickets chirped in the searing Texas heat as the Sunday service was held in the Johnson family cemetery, where the late president and more than 30 other extended family members are buried. Lyndon Johnson died in 1973.
Johnson was president from 1963-69. Once he left office, he and Lady Bird Johnson retired to the ranch and Austin.
Lady Bird Johnson's casket, topped with multicolored flowers, was carried to the grave site by military body bearers. Along with Nugent's remembrance, prayers and the singing of "Amazing Grace" completed the brief service.
As they departed, daughters Luci Baines Johnson and Lynda Johnson Robb smiled and greeted a few of the about 300 people attending the service.
Earlier in the day, thousands of admirers, many clutching bundles of wildflowers and American flags, lined streets in Austin and roads in the Hill Country as the former first lady's body was brought from the state capital to the LBJ Ranch, about 70 miles west of Austin.
Members of the crowd applauded and cheered as the procession passed through downtown Austin, and a few women blew kisses. Motorcycle police officers escorted the navy blue hearse that displayed a cluster of little orange wildflowers on top. Johnson family members followed in two limousines and waved to the crowd.
"It's the passing of an era," said Sarah Macias, 48, who works for the Austin parks department and came to watch with her husband and a co-worker.
Retiree Kate Hill handed out sunflowers from her garden to people waiting for the procession in downtown Austin. Hill said Johnson's work inspired her to convert her grassy lawn into an expanse of wildflowers and other native plants, and she wanted to thank the former first lady for the beauty.
Along the cortege's Hill Country route, well-wishers waited in lawn chairs and set up greeting signs.
One sign atop a tractor on a rural stretch of roach read "Thank You Lady Bird." Another said, "God Bless a Great Woman."
In Johnson City, President Johnson's boyhood home, a main street was lined with little Texas and American flags stuck in gravel-filled flower pots.
The procession and burial capped three days of ceremonies that started Friday with private family prayer services then a public visitation at the LBJ Library and Museum.
On Saturday, she was eulogized in a two-hour funeral service attended by former Presidents Bill Clinton and Jimmy Carter, First Lady Laura Bush and former first ladies Rosalynn Carter, Nancy Reagan, Barbara Bush and Sen. Hillary Rodham Clinton.