Betti Wiggins was preaching to the choir, singing the praises of school gardens.

And the choir was hanging onto each note, they being the eager teachers and representatives of 45 Minnesota schools, nearly 400 of them hungry to introduce their students to this hands-on learning experience.

Wiggins, executive director of the Office of School Nutrition for the Detroit Public Schools — or, as she calls herself, the head lunch lady — brought her experience and enthusiasm to the fourth annual Schoolyard Garden Conference, held recently at the Minnesota Landscape Arboretum.

Had the weather been a bit warmer, Wiggins no doubt would have put the participants to work.

Today, though, she fielded questions from her pulpit. "Children have a right to fresh fruits and vegetables," she said.

The day before she had toured Roosevelt High School's greenhouse and indoor aquaponics "farm," where she was impressed by the students' skills.

Back home in Michigan, Wiggins created the Detroit School Garden Collaborative in 2011, which today supports 79 gardens and a 4 ½-acre farm that provides some of the food she feeds to 46,000 students daily.

Wiggins, a master gardener herself, grew up on a Michigan farm, so she's no stranger to the effort needed to maintain a garden.

At the conference, she offered specific recommendations on how to increase the 80-plus school gardens in Minnesota.

What's your lunch program like?

Wiggins serves breakfast and lunch to all students, as well as supper for 7,500 of them. She chose to provide supper rather than snacks because of the funding that goes with it. With 100 percent of her students receiving free meals, she knows where her dollars are coming from. "That's my business model. You can't have a successful program without money," she said. "These dollars are the kids' money. I invest it back into the program for them." That includes funding the garden program.

What about communities that want to start up school gardens but don't have a large number of free or reduced-lunch participants?

"Add a 'tax' to school lunch," she said. Charge an extra 5 cents per meal and direct it to the school garden. "Parents will thank you. There's no need for a fundraiser then."

Do teachers run the garden program?

"No, teachers have enough to do. We can't ask them to do a garden, too. We need a staff to do it, and that costs money," she said. Wiggins has seasonal garden attendants (she calls them G.A.s) who are paid to take care of growing produce and to meet with schoolchildren. "That gives accountability on both sides. If a teacher commits to taking their children to the garden and a G.A. is waiting there, it's harder to skip doing it."

Do the school gardens save money?

"They weren't started to save money, but to give young people an opportunity. I give my budget credit when using lettuce from the farm. But child nutrition should not be a moneymaker." Any surprises with the gardens?

For the first year, in the excitement of planting, she overlooked the fact that the big harvest would be before the children were back in school. So they picked the produce and brought it to food banks. With the school timeline in mind, they now adjust the farming schedule to plant earlier or later so the harvest doesn't occur when students are away. To do this, they use temporary greenhouses to manage the plantings. They also look for crop varieties that suit their timetable. Even a 10 day-difference is significant.

Do you have a nutrition or garden educational program?

There is an approved curriculum that teachers use in the classroom and that covers both nutrition and gardens. "It has to be institutionalized, or it would die when the driver leaves," she said.

What are the benefits of the school garden?

There's fresh produce that can be incorporated into school meals and a greater understanding of fruits and vegetables for students. They end up promoting healthful food to their families.

Does the collaborative operate on its own or have help?

The program creates partnerships, including with 4-H and the Michigan Extension program to provide Junior Master Gardener courses at the schools. They also partner with the Detroit Public Schools Office of Science to provide professional development for teachers not only about gardening but for teaching science classes related to plant biology. Food Corps provided two staff this school year to teach nutrition education and garden skills. Other community partners assist financially, as well.

What about the farm?

They grow non-GMO corn, butternut squash, salad greens, potatoes, watermelon, collards, kale and mixed heirloom vegetables, as well as the ingredients of what they call their "stoplight" salad (yellow squash, zucchini, cherry tomatoes). The farm also grows what Wiggins call the DPS [Detroit Public Schools] salad mix (baby spinach and lettuce). Last year the farm raised more than 30,000 pounds of food; more than 7,000 pounds was donated or given to food banks. They use only organic approved sprays and crop treatments.

Are you really feeding the district with the school gardens?

"We allow the younger kids to feel like they are feeding all the district, though they are not really," Wiggins said. At individual schools, she requires that they grow the ingredients for the "stoplight" salad, which are served at the home school. Other vegetable or herb plots are determined by the schools themselves.

What garden activities do you plan for schoolchildren?

"We do a field trip with 100 kids. We drive 185 miles and then pick blueberries. Kids get to eat as many as they want, and bring some back. Then we drive home. They love it."

Lee Svitak Dean is the Star Tribune's Taste editor. Reach her at lee.dean@startribune.com or follow her at @StribTaste • 612-673-1749 Facebook: Star Tribune Taste