Friday marks three years since two bombs exploded near the finish line at the Boston Marathon.
Of the many tributes since then, none is more colorful than the return of the daffodils to the city and suburbs that are the route of the race.
The daffodils in bloom throughout Boston mark more than the change of seasons, reports CBS News correspondent Michelle Miller.
"The daffodils symbolize hope and rebirth. They're incredibly cheerful, they are also incredibly tough," said Diana Valle, who started the "Marathon Daffodils" project after the bombings in 2013.
"I hope people will see it as a beautification that can continue and that other people will plant their own daffodils along the route," Valle said.
More than 100 volunteers from the eight towns along the marathon route pitched in to plant as many of the resilient perennials as they could.
"The idea grew from a few to 100,000, from Hopkinton to Boston on 26.2 miles," Valle said.
Potted daffodils - grown and kept cool at a greenhouse south of the city - are timed to bloom just before the race.
"Once they get out in the warm air, they will open and be full of color," Valle said.
More than 2,000 will go to businesses along the route, like Marathon Sports - the finish-line storefront where the first of the two explosions took place.
Shane O'Hara was there three years ago, sheltering survivors and tending to the wounded.
"I don't think I did know what I was doing. It was more of reactions," O'Hara recalled.
O'Hara has fielded questions about what happened in front of his store since the bombings took place. When the daffodils arrive, he gets to share a different story.
"When we line them up, it's a nice yellow life, just like the sun. Who doesn't smile when the sun's up?"