"Nature gave us the perfect art form. Nature doesn't make any mistakes," she says smiling.
Trained in Japan, she's brought her creations to life over four decades at the de Young Museum's annual "Bouquets to Art" exhibit.
"Still a little touchup I want to do, but it's OK," she says, showing off this year's arrangement.
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Now in its 40th year, the "Bouquets to Art" infuses floral arrangements to mirror and celebrate traditional works of art. From the vertical elegance of classical statue, to a field of billowing cotton balls captured in an oil painting, the arrangements add a new dimension of shape and color to the artworks they're placed in front of.
"And so, you study that for a little while, and then you start coming up with ideas," says arranger Michael Daigian.
His arrangement combines cactus with a painting of Mexican revolutionaries.
"You know, and that was it. That was a rare find. We found that at a nursery about a week or two ago," he says.
For creator Leslie Kaye, images of the metal hardware on a rooftop became the vase and stand for her arrangement.
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"We knew we wanted tall rectangular copper. The inspiration was this copper rectangle that's all weathered," she says, pointing to a section of the painting.
And with all its creative challenges, the exhibit has grown in popularity over the decades, drawing tens of thousands of visitors and critical support for the museum.
"Over the years, 'Bouquets to Art' has raised something like $9 million for the fine arts museums, and its art in its own right," says Thomas Campbell, director of the Fine Arts Museums of San Francisco.
Crowds of floral artists converge on the de Young, in a mad rush to set up the temporary exhibits, plucking, placing and rearranging, sometimes, over and over again. And in the end, Soho Sakai believes the perfectionism is mirrored in the joy the flowers create.
"I think when you see something, a perfect art form, I think you become happy I believe. I you are not, something's wrong," she says.