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The Daily Wildcat

The Daily Wildcat


Get to know the Student Union’s rooftop garden before it opens in December

Emily Chressanthis
The garden atop of the Student Union Memorial Center is set to open sometime in mid-December.

The rooftop garden atop the Student Union Memorial Center, designed and run by students, has provided fresh produce for the University of Arizona community for a year and was inspired by the UA Campus Pantry, according to Todd Millay, director of the Arizona Student Unions.

“We have a lot of food-insecure students on campus, grad students, faculty and staff, undergrads that don’t have access to food and nutrition very well. And the Campus Pantry … is really the reason this is even occurring, because we’re trying to produce fresh vegetables and produce that we will harvest from here and send downstairs to the pantry,” Millay said. 

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Millay said that there is a harvest every week and the design for the garden was chosen through a campus-wide case competition about 18 months ago. A hundred and twenty-five students, self-formed into groups of five, participated in this competition, and the judges were master gardeners from Tucson and engineers.

“The top five teams got to present in Gallagher Theater after they made their way through the competition. Big audience that night. The winning team suggested this, and so we literally built the winning team’s idea. So this is a student idea, actually — pretty awesome,” Millay said.

The garden is about 1,000 square feet, housing a little over 200 plants. The vegetables grown include bell peppers, cherry tomatoes, slicing tomatoes and mini-cucumbers. The garden only uses natural sunlight, and nutrients are recirculated with a loss of only five percent, according to Millay.

“This is all grown hydroponically … there is no soil here. What we are growing in is called rockwool, and it is a volcanic rock that’s heated and spun. It’s kind of like the pink insulation material that you can buy at Home Depot or Lowe’s for your house, but it’s processed just a little bit differently to grow in,” said Stacy Tollefson, the project and production manager for the greenhouse and a professor in the Department of Biosystems Engineering.

Rockwool does not provide any nutrients, so the plants are fed an inorganic nutrient mixture that is hooked up to a timed system. The plants also take in fertilizer. 

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All varieties grown in the garden are non-GMO hybrids, meaning that different species were naturally cross-pollinated and are without genetic modification. About 3,000 pounds of cucumbers, 1,200 pounds of slicing tomatoes, 800 pounds of cherry tomatoes and 250 pounds of peppers are grown annually.

“The nice things is that we are doing this for students [in] need, and faculty or staff [in] need, and that’s great. We don’t have to worry about having to sell stuff and getting a profit and that kind of thing. This is grown by students, for students. Closing that loop is great,” Tollefson said.

Tollefson recruits new interns each semester, and interested students can contact her for an application. Interning students can gain experience with growing produce and with hydroponics, as well as earn engagement credits. Tollefson can be reached at

The garden has not yet set a date for its official opening.

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