First lady Michelle Obama, joined by school children from across the country, harvests the White House Kitchen Garden on June 6. (Andrew Harnik/AP)

The tomato and pepper plants are basking in the steamy heat, but before the gardener can think of summer, there’s the spring harvest to gather.

On Monday, 10-year-old Trenity Tillahash plucked the turnips before moving on to the kale and cauliflower. At her side was the nation’s gardening-advocate-in-chief, first lady Michelle Obama. “It’s changed a little bit since April,” Obama announced, in an understatement, to Trenity and two dozen other fourth- and fifth-graders who had arrived at the White House Kitchen Garden to reap the veggies. “I told you it was going to be something really different.”

A cool, damp spring — kicked in the pants by a hot spell — had together worked their magic. The pea vines were six feet tall, the cabbages were broad and leafy, and that finicky orange-curd cauliflower had headed up nicely.

It would be easy to assign this horticultural virtuosity to the team of professional gardeners who tend the beds, which are nestled in the southwest corner of the grounds. But Obama seemed to move from one raised bed to another with the ease and confidence of a seasoned gardener. Eight years into high-profile vegetable gardening, Michelle Obama knows her onions, as they say in England.

The kitchen garden is the most tangible element in her crusade to introduce the nation’s children to a better diet and more exercise, and Monday’s harvest event was held with children from Wisconsin, Colorado and Louisiana who have active schoolyard gardens, along with her regular gardening buddies from Bancroft and Harriet Tubman elementary schools in the District. For good measure, she was joined by TV celebrity chef Rachael Ray and Frankie Celenza, a star chef for the multimedia Tastemade food network, who calls himself “the food ambassador of my generation.” He’s 29.

Obama has been a high-profile ambassador herself, championing fresh, nutritious food. But at these White House harvest events, she takes the idea of farm to table literally. After the harvest, the children helped to chop the veggies before throwing them into skillets where half a dozen White House chefs concocted a spring vegetable curry and a fresh salad stocked with just-pulled vegetables. At one point, Obama and Ray were elbow-to-elbow, stirring the skillets. The ranks of press photographers clicked away.

The spring harvest is typically the middle of three such events annually in this most utilitarian of White House landscape features and marks the final spring harvest for Obama. One hopes the next incumbent will keep this inspiring garden going.

For all the stage management of the events, they are especially meaningful to the young people who participate. Trenity is from a rural population in southwestern Colorado that is largely Native American and agricultural, but in danger of losing its agrarian traditions. “Our hope is to reconnect them to their agricultural heritage,” said Danyel Mezzanatto, who coordinates the school garden at Trenity’s elementary school in Cortez, Colo., and was at the event as a chaperone.

Obama seemed to acknowledge the far-reaching symbolism of the kitchen garden in her remarks to the kids. “A lot of schools and communities are doing what we are doing here, so you guys are champions in that effort.”

Trenity said she was thrilled working the garden with the first lady. “And I did meet Rachael Ray, and I told her that my mom really loves her and has been watching her cooking shows since before I was born.”

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