Yoko Ono embraces peace, health, prosperity, and wishes, but she can do without sunlight. Descending to the Hirshhorn’s sculpture garden for a press event this afternoon, the petite conceptual artist and rock-star-by-proxy was protected by an umbrella, carried by a factotum of her “Imagine Peace” and “Wish Tree” projects.

Ono’s wish trees arrived in Washington for the Cherry Blossom Festival, which has designated 10 blossoming cherry trees around the Tidal Basin as places for people to attach small pieces of paper containing their written wishes. An 11th wish tree, a white Japanese dogwood in the sculpture garden, is a permanent addition to the Hirshhorn collection. According to Hirshhorn curator Kerry Brougher, who spoke at a press conference following the event, “It’s a major piece.”

Before today, it was a tree, but Ono made it a “piece” by writing a wish and attaching it to a branch. (What did she write? At the press conference, she invoked a “don’t tell” policy.) Others will be encouraged to add their wishes, which will “harvested” by Hirshhorn staff. Ultimately, the hopes and pleas from all of Ono’s designated trees will be stored at the library of the Imagine Peace Tower in—-where else?—-Reykjavik.

Dressed all in black save for a shiny silver jacket, Ono looked like an art star but acted more like a schoolgirl. As Hirshhorn Director Olga Viso explained the wish tree concept, the artist giggled, shrugged, and nodded. Her own comments in front of the tree were largely inaudible and over in about a minute.

At the press conference in the museum’s auditorium, Ono had the benefit of a microphone, and discoursed at more length on war, peace, and the wish trees. “I never thought this was going to be my ‘hit record,’ ” she said of the project.

If the wish-tree concept is a hit, it’s a cover version. As she concedes in a press release that was distributed at the event, tying wishes to trees is commonly done at Japanese temples and shrines. The only difference is that, at Japanese sacred sites, the wishes are more commonly known as prayers.

Questioners solemnly queried Ono about war and peace, and asked her what John Lennon would have thought about the conflicts in Iraq and Afghanistan. She was not reluctant to answer for the dead Beatle—-he would have disapproved—-but quickly brought the subject back to her. The casualties in those countries, she said, are like her and son Sean’s loss of John.

From her early days as a member of the radical Fluxus movement, Ono has softened into a sort of new age Marcel Duchamp: still conceptual, but now rather squishy. Her notion that people can create a better world simply by visualizing it sounds a lot like current self-help claptrap The Secret. “We should all wish for a beautiful, beautiful, healthy world,” she said, and her only explanation for why such wishes don’t seem to have any effect is that people mistakenly think about the bad things they want to abolish instead of the good things they want to encourage.

As proof that visualization can work, she offered smoking bans. “We never thought that people could stop smoking,” she argued. “But it only took about five years. So what about world peace?” (Uh, five years counting from when? And don’t people still smoke?)

“We’re all artists,” Ono explained, and Brougher noted that the wish tree is a characteristic Ono piece, in that the viewer becomes a participant and “completes” the work. There was no participation at this high-security event, however, as Ono was escorted from the auditorium, a flaw in her logic became clear: We all may be artists, but we’re not all celebrities.