The way food is growing is changing. Labor constraints or increased water regulations out west are some of the catalysts behind that shift.
At the University of Minnesota, researchers are experimenting with new technology to help growers use less water and produce more food — but all indoors — and it’s opening a new field of opportunity to change the way food is grown.
Taking Controlled Environment Agriculture Into Uncharted Waters
Controlled environment agriculture (CEA) isn’t new, but with a renewed focus, there’s a revolution in how it’s used.
Just take the University of Minnesota for example. Step into one of the many greenhouses on campus, and one in particular doesn’t look like the rest. There are bright lights and various crops being grown indoors, but there’s something missing in this particular greenhouse: soil.
“One of the major factors that we have going on is hydroponics here. Hydroponics is literally water working. In Greek, that’s what it means, working with water,” says assistant professor Nate Eylands. “And so a lot of our plants here, if I were to pull these out, there is not a soil substrate in there. It is pretty much just roots hanging out in water. And so in order to do that, what we need to do is take all the traditional benching out of here and put in our own systems here.”
Eylands says hydroponic systems like this use a fraction of the water compared to traditional agriculture. The benches he crafted just for his research are angled at about two and a half degrees slope. He says that allows the water to gravity feed down to a drain, then it’s pumped back up to the beginning. It’s a recirculating system that saves on water, nutrients among other resources.
“Having this recirculating system is probably that primary benefit. We’re able to use about 9[%] to 10% of the water that you would for growing these per kilogram basis, per biomass basis — this 9[%] to 10% of that water that use out in the field,” he says. “We’re not having any runoff. Any of our nutrients aren’t leaching out into our environment, into our waterways. So by recircling, we’re only providing and the plants are only taking what they need at that very moment.”
The Introduction of Quantum Dots Sounds Crazy, But It’s Showing Promise
But saving water is just the start. Eylands’ team is experimenting with quantum dots — microscopic particles that transform light to make plants grow faster.
“Quantum dots are little nanoparticles, and they absorb photons of light and change that photon into a different photon,” Eylands says. “Say you have blue light coming in, it might be red light coming out of it. So, what we’re doing is taking a liquid quantum dot and we’re spraying it on some of these plants. You can’t tell which ones of them have it. And then on the leaf surface, they are absorbing that photon, say a blue photon, and converting it to a red photon. And that might speed up the process of photosynthesis at different stages of the plant growth.”
By altering the light spectrum, researchers hope to speed the flowering on these plants — boosting yields and making indoor production more efficient.
“What we’re trying to find out is: Can we get to an earlier flowering time? Can we get more fruit out of an individual plant? Can we speed up the vegetative cycle? Can we do any of these phenology benefits that help growers out in an economical way that leads to profitability?” Eylands continues.
Today, that research is being done on tomatoes. While it’s in its early stages, the goal is for this research to reach commercial tomato production.
“We have a lot of different factors that might inhibit that right now. For one, we don’t really know the cost of this,” Eylands says. “It takes a plasma reactor to make these quantum dots. It’s very arduous, very difficult. We have plasma physicists over on the East Bank making these quantum dots, so it’s not something that I’m making in-house. However, through these collaborations, we’re able to get our hands on some of these and formulate some of this to work with plant growth.”
The Goal? Make Controlled Environment Ag More Profitable
The larger mission, Eylands says, is clear: make controlled environment agriculture more profitable for commercial growers — and bust the myth that growing indoors doesn’t pay.
“In controlled environment agriculture, we run into a problem of profitability. The economic model always has to work out,” Eylands says. “We pay for lights, we pay for infrastructure — all this equipment around us. That capital cost is pretty expensive. So, what I want to see is more productivity out of these plants so that when we look at production costs overall they come down for growers.”
One example in the Minnesota greenhouse: dwarf tomatoes growing in systems designed for leafy greens. Eylands says this approach could open new opportunities for farmers.
“What I think is really cool about this project is in most cases what you’re seeing in tomato growth is these tall houses with vining structures to trellis these tomatoes,” Eylands says. “They might be harvested on scissor lifts that are 20' tall. So, what we’re doing here is we’re also showcasing a way that you can take a setup that was made maybe for leafy greens like lettuce or kale or bok choy, something of nature, and allowing those growers to diversify their crop offerings by saying, ‘Hey, look at these dwarf tomatoes. These fit right in your your NFT (nutrient film techniques) hydroponic system here,’ so it’s allowing them options out there. Is this economic model going to work? If you can’t quite sell all your leafy greens, maybe sell.”
From light-bending nanoparticles to water-saving hydroponics, the work at the University of Minnesota could reshape how America’s produce is grown — and take profitability, for those growers, to new heights.
