On a secluded desert road in Marana, a vision to produce sustainable food that relies less on traditional field agriculture and more on soilless plant farming is slowly taking shape.
Hydroponics is the technology that Brian Sternberg and Stacy Tollefson will use to grow most crops at Maggie’s Farm Arizona, spread across 22 acres on Maggie’s Farm Lane. Instead of soil, the method uses a nutrient-rich solution to deliver water and minerals to plant roots. But that’s not to say the farmers will abandon conventional ways of farming altogether.
“We’re doing a little bit of everything, but the hydroponics is going to be the biggest way that we grow,” Tollefson says. “It’s the most stable and reliable way to get nice quality product out all the time.”
Tollefson, who teaches hydroponics courses and manages a greenhouse at the University of Arizona, began doing consulting work for Sternberg in 2012. Early this year, she became a partner in the business venture.
Walking around the property with Tollefson one morning, Sternberg says the goal is to transition Maggie’s Farm into a full-fledged commercial operation. Since he bought it in 2011, it has operated much like a hobby farm.
“A lot of it has been experimentation, trying to figure out what works and what doesn’t work,” he says.
What became problematic after some time was the farm’s aquaponics system, which combines the raising of fish—aquaculture—and hydroponics. Sternberg and Tollefson enter into a spacious greenhouse where the smell of basil and mint permeate the air. Inside, worker Sandy Bales for four years grew the herbs and various lettuce varieties using fish waste as nutrients that flowed to plants growing in soilless beds. The plants then purified the water and returned it to nearby big fish tanks.
But something went awry. “We had different species of fish—tilapia, koi, and goldfish,” Tollefson says. “The fish started mating and laying eggs in the system and the eggs and the babies were getting into the troughs and they were eating the roots. It was just a constant maintenance issue to get the fish out of the troughs all of the time, and so we basically had to shut the whole system down.”
The farmers plan to redesign the system at some point, but will reduce it from three greenhouses to a single one.
“One of the reasons we’re doing that is because nutrition in the winter in the aquaponics system really goes down,” she says. “The fish just don’t eat as much in the cold weather, so it’s harder to maintain a healthy crop during the winter.”
For now, they are using the troughs from the aquaponics system to grow plants hydroponically. “It’s still a floating system, but instead of using the aquaponic water we’re using the inorganic mineral salt, the regular hydroponic nutrients in those,” Tollefson says.
Even as the farm expands, the farmers say experimentation isn’t likely to end. “Really, the hydroponics will give us the most stability for income because it’s a year-round production,” Tollefson says. “Then we can supplement with field incomes and have some cool different things.”
Like edible flowers. “Right now we’re experimenting with them,” Sternberg says, entering a small propagation greenhouse filled with seedlings.
The blooms—nasturtium, borage, Thai basil—are for the Ritz-Carlton, Dove Mountain, in Marana, where they’re added to drinks. From what Sternberg hears, the edible flowers have been a hit.
The farmers also cultivate moringa plants, whose leaves are used to make a protein powder, in a small field. And in a temperature-controlled space nearby, pearl and blue oyster mushrooms grow in spawn bags.
The bags come from UA students, but the farm is bolstering its mushroom operation and will start making its own bags, says worker Ryan Capistrano. As part of the changes and renovations, the farm’s animals, mostly sheep and a couple of burros, are gone.
“We really want to focus on produce,” Sternberg says. A flock of chickens, still clucking in the coop house, might stay. “People like the eggs.”
The eggs and many other vegetables, including cucumbers, peppers, lettuce, eggplant, and herbs, are sold at the Santa Cruz River Farmers’ Market at Mercado San Agustín. The farm also supplies restaurants and other local markets.
The two new hydroponic greenhouses started going up in the summer to grow the bulk of crops. Much of the planting will be done in November and the harvest will start in February, Tollefson says.
“We will have about 2,300 pepper plants, 300 cucumber plants, and 1,300 tomato plants,” Tollefson says.
She calls the hydroponics system much more stable than aquaponics. “We can count on that fertilizing the plants and having the crops all the time, whereas the aquaponics—it fluctuates quite a bit.”
Increased consistency bodes well for production. The expectation is that the two greenhouses each month will yield about 2,000 pounds of tomatoes, 1,500 pounds of peppers, and 600 pounds of cucumbers.
Although the vegetables are not grown organically, she says the farm’s practices include few pesticides. “We either use no pesticides, if possible, [or] if we need to use pesticides we try to use stuff that’s labeled organic, and we try not to use synthetic pesticides at all.”
Growing organic hydroponics is not an industry standard right now, she says, but it is something she continues to research at the UA.
Future farm endeavors also include a new stock of fish and freshwater prawns, as well as opportunities for people who are interested in farming.
“The main vision is to be a model sustainable farm, with multiple methods that we grow, with multiple income streams. But also to be a model to show people different ways that you can farm,” says Tollefson. “We want to have classes to teach people how to grow mushrooms and teach them how to grow hydroponically and aquaponically, as well as different permaculture techniques for field growing.
“We want to grow vegetables, but we also want to be an educational center.” ✜
Maggie’s Farm Arizona. 520.591.0085. Visit MaggiesFarm.com for information about monthly tours.
Lourdes Medrano is a freelance writer based in Tucson. Follow her on Twitter: @_lourdesmedrano