"I made a statement recently which I'd like to retract," declared Joni Mitchell on Tuesday night, onstage at Toronto's Massey Hall. "There's a lot of those." The one in question, from a recent CBC interview, was that "Honour died in World War II;" after watching singers such as Rufus Wainwright and Kathleen Edwards pay tribute to her songs with a crack eight-piece band, Mitchell pronounced herself "deeply honoured and very happy." Another retractable statement — derived from that same interview — would be, "I can't sing."

Originally, Mitchell had announced she would simply recite a new poem at Joni: A Portrait in Song, a birthday celebration (Mitchell turns 70 this year) organized by producer Danny Kapilian and the Luminato Festival. Years of illness, she claimed, had left her with an "instrument" that she couldn't control, and it had been over five years since her last public performance. But at Massey Hall, she also sang three songs to a happily startled crowd. After speaking her way through the first three lines of her 1976 song Furry Sings The Blues, she assayed one of her trademark melodic swoops — on the lyric "faded out with ragtime blues" — to resounding cheers. The song's original recording exploits the difference between her own soprano and the "muttering" of a "down and out" singer; now, her lived-in voice, intimate and dusky, offers some poignant common ground.

Mitchell appeared two hours into the nearly three-hour concert, smiling and sashaying in a grey dress that looked both smock-like and regal; she praised the "beautiful and individuated performances of my music" she'd just heard. The tribute, directed by drummer and longtime Mitchell associate Brian Blade, featured artists who had not only mastered the devious twists in her charts, but also inhabited them with their own voices.

Before singing Mitchell's deceptively complicated The Boho Dance, The Swell Season's Glen Hansard admitted it had taken him a month to learn the material: "I think in 1's and 3's and 4's, and she doesn't think like anyone." He and his fellow singers met the challenge head-on; their most memorable renditions were reinventions. Wainwright turned the percussive Slouching Towards Bethlehem into a haunting "Scottish folk song" (recalling his own elegiac Candles); Lizz Wright delivered the ethereal Shades Of Scarlett Conquering with a rich, soulful warmth in her honey-like alto; and in a potential star-making turn, Toronto's Cold Specks interpreted Black Crow as a lugubrious, fractured folk tale, both soulful and gothic.

Mitchell herself brought an energetic earthiness to her lilting Don't Interrupt The Sorrow, and along with the whole company, including rocker Liam Titcomb, she sang Woodstock as an atmospheric piece, its longing tempered by wisdom.

The best that can generally be said about tribute concerts is that by recasting the music in an exciting light, they encourage you to revisit the artist's back catalogue with new ears; Luminato's celebration may have gone even further by inspiring its dedicatee. "This is so much fun," said Mitchell.

Her new poem, This Rain, This Rain, backed with a beat-style vamp, brought together her devotion to painting, her love of seclusion, her propensity for complaining (in interviews, at least), and her playfulness, drawing on a passage from Emily Carr's journals about bad weather in B.C. Mitchell mentioned the poem didn't have "a melody written yet" — offering hope that one day, she'll sing a new song. Now that would be some retraction, like paradise unpaved.