How can leafy lettuces, perky sprouts and fresh herbs be local in mid-winter?

Even in the depths of this chilly season, vibrant local greens are growing. Along with the more familiar hydroponic method of cultivating greenhouse plants in water, there’s a newer technology that relies on air: aeroponics.

Living Greens Farm in Faribault, Minn., uses aeroponic farming methods to produce salad greens, sprouts and herbs. The plants are seeded in “rockwool,” a lava-like medium that allows for more oxygen than does soil or water, and their roots are nourished with naturally fortified mist.

“With this sustainable, indoor vertical farming platform we can grow and harvest the same amount of salad greens on one acre of our farm as a traditional farm can grow on 200 acres,” said Michelle Keller, head grower.

“Plant roots need access to a lot of oxygen to absorb nutrients. The challenge with traditional soil growing methods is that the oxygen is reduced by as much as 70 percent. With aeroponics, the plants receive all the oxygen they need. The result is that the plants grow 100 percent faster than in soil and 50 percent faster than in water. They end up being more robust and healthier, too,” she said.

Aeroponics uses 95 percent less water, and no pesticides, herbicides or chemicals, according to Keller.

“The best thing about this technology is that the growers can give the plants exactly what they need when they need it,” she said.

Keller seeded her career at Crop King shortly after graduating from the University of Wisconsin-River Falls in 1996. She set up her own greenhouse in 2004 and founded LaBore Farms, which grew a variety of greens hydroponically. She sold it in 2010, before moving on to Living Greens.

These salad greens are as flavorful as those grown in a garden, unlike many of the hydroponic greens that wilt quickly and often lack flavor. Living Greens watercress is especially peppery, the arugula is snappy and tart, and the red oak and leaf lettuces made a fine salad and wrap.

With the greens shipped as soon as they’re ready, they are far fresher than any from California. Keller, a plant scientist, is responsible for the nourishing formulations and is known as “the plant whisperer” by her colleagues.

The only thing Keller misses is being outside. “I work with the plants all day inside, under grow lights. It’s great, but it’s not outside.”

Living Greens produce is in local food co-ops. The lettuces are available in 5-ounce packs for about $4; the microgreens in 2-ounce packs are about $5.50. For more information, see