Urban Growth

MetroGrow Hawaii

A hidden farm in Our Kaka‘ako presents viable solutions to traditional agricultural obstacles.

Text by Brad Dell | Images by John Hook

Kaka‘ako was home to wetland agriculture and salt ponds long before it was enveloped by cityscape. As I sit in a warehouse in the neighborhood and bite into just-picked lettuce still covered with saltwater droplets that shine like crystals, it’s easy to imagine what fresh harvests of the land once tasted like. Except that this lettuce, an ice plant (aka glacier lettuce), didn’t exist in the islands until Kerry Kakazu, owner of MetroGrow Hawaii, began growing it in his indoor vertical farm.

MetroGrow Hawaii, which Kakazu founded in 2013, uses aeroponics, a growing method in which plant roots are exposed to air and periodically misted with a nutrient solution. LED bulbs replace sunlight, fans and tarps keep varying air temperatures cool, and advanced delivery systems minimize water and fertilizer usage. These practices allow Kakazu to grow cool-weather crops year-round, such as mache, smooth-leaf spinach, and miner’s lettuce. Kakazu says his is the first legal farm of its sort in the state. “Before, it was just the marijuana growers doing this,” he says with a laugh.

Rows of lettuce and shoots line the racks of Kakazu’s indoor farm, which is located in the same structure as Kaka‘ako Agora. It looks more like a laboratory than a greenhouse, with purple and pink microgreens sprouting from plastic pods, and Kakazu controlling the conditions— from the intensity of the lighting to the frequency of nutrient misting—with quick swipes on a smartphone. The innovative farmer has a doctorate in plant physiology, but admits that technology has gifted him with an artificial green thumb. “People used to always ask for advice on how to grow plants,” he says. “But I was always grinding them up, killing them, and analyzing them. I would always say, ‘Don’t ask me!’”

Before launching MetroGrow Hawaii, Kakazu worked at the University of Hawai‘i Cancer Center for 13 years, where he researched cell division and managed facilities. In 2013, he noticed the growing demand for local foods and took the opportunity to open his first-ever farm. What began as a hobby for Kakazu became a full-time profession within a year. After a period of trial and error, he became confident in manipulating the environment of crops to change sizes, colors, and tastes— an ability that has made his business popular with eateries that desire unique food aesthetics, such as sushi restaurants.

This revolutionary farming method also supports sustainability and healthy eating. The plants don’t require pesticides and consume less fertilizer, water, and land than traditional farming. Kakazu says these factors are increasingly important in the face of land and freshwater shortages, as well as increasingly humid, stormy days in Hawai‘i, which create an unstable outdoor growing environment. Kakazu sits behind his desk, looks at his plants, and says, “This could very well be the future.”

MetroGrow Hawaii


Microgreens are plants that are grown to the point where the first set of true leaves (the second set of leaves that grow from the sprout) have emerged. They are usually even more flavorful than the full-grown plant, and are best eaten fresh as garnishes or added to salads. Plants in the cabbage family, like radish, kale, and arugula, make for hardy microgreens, which are ready within 10 to 14 days. For shoots, pea, sunflower, and soybean are good options, and are ready in about 10 days.

Step 1: Soak the seeds overnight in water. (Smaller seeds and mucilaginous seeds like chia don’t need to be soaked.)
Step 2: Spread seeds generously on potting mix in a shallow tray, such as nursery trays available at garden shops.
Step 3: Cover with a thin layer of potting mix.
Step 4: Cover with plastic or another inverted tray until seeds sprout.
Step 5: Uncover and keep well watered.
Step 6: When ready, cut shoots and microgreens with clean scissors.


It starts with the soil. For a DIY mix, many people recommend a mix of coconut coir or peat moss (moisture holding), compost or vermicompost (organic matter), and perlite (drainage). A little bit of fertilizer can be added to the mix, but since most leafy greens grow quickly, you don’t need to add much.

Then, the container. Because you are growing in a container, plants can easily be overwatered. (Potting mix should be moist, not soaking wet.) Containers should have ample drainage. The plants can also get hot if outdoors, so for Hawai‘i, use lighter- colored containers if available.

What about growing indoors? You need either a sunny window or electric lights. LED or fluorescent lights work fine.

Additional recommended resources: University of Hawai‘i O‘ahu Urban Garden Center, local nursery and hydroponic stores, Koolau Farmers, Ohana Greenhouse & Garden Supply, and Hawaiian Hydroponics & Garden.

For more information, visit metrogrowhawaii.com.