First lady Michelle Obama, left, and astronaut Cady Coleman welcome students to help plant the White House Kitchen Garden on Tuesday. (Jim Lo Scalzo/European Pressphoto Agency)

THE IDEA eight years ago, according to first lady Michelle Obama, was to “dig up some dirt on the South Lawn” and plant a garden that would be “a space for us to talk about the food we eat.” This being Washington, nothing is ever taken at face value: There was speculation about hidden agendas (advancing leftist causes), criticism about gardening (too trivial to be a priority for the first lady), self-interested lobbying (from promoters of pesticides aghast at plans to go organic) and dire predictions (the garden would be short-lived once the first family found out weeding is a chore). There were even conspiracy theories after the first harvest proved so bountiful that skeptics were sure it had been trucked in.

But in the real world, the White House Kitchen Garden has more than lived up to its mission of encouraging a national conversation about healthy eating. We hope, as Ms. Obama said she does, that this year’s planting won’t be the last. The next first spouse should recognize the value of the garden and turn Ms. Obama’s delightful contribution into a tradition.

“This is my baby,” Ms. Obama said Tuesday at the planting of the kitchen vegetable garden that will be her last as first lady. As is the custom, she was joined by schoolchildren — including some of the D.C. students who helped with the first garden in 2009. “You might be a little more interested in eating your vegetables if you know what they look like,” said Ms. Obama.

The exuberance of those children in lending a hand while learning about nutrition and interacting with the first lady is one reason the garden should continue. The cost in seeds is minimal; the produce feeds not only the first family and official guests but also residents of area homeless shelters. Besides, there is something “very American,” as one writer observed in the New York Times when the garden started, about its “simplicity and beauty and self-reliance.”

To be sure, not every White House occupant will share Ms. Obama’s love of digging in the dirt. But the garden has been successfully maintained with help from staff and volunteers. And perhaps Ms. Obama, who plans to stay in Washington until her younger daughter finishes high school, could drop by from time to time with her trowel and lend a hand.