At first glance, the grange at 1015 Half St. along Washington DC’s southwest riverfront looks like any other lush urban garden: neat rows of kale tightly sowed near brambles of mature thyme with pastel flowers. Yet this farm can only be accessed by elevator. One ride to the top of an unassuming 12-story building, with a Chicken Bon Chon and physical therapy office on the street level, is a verdant Eden in the nation’s capital.

“We grow a ton of kale, and we grow peppers. They absolutely love it up here,” said Nick Berini, a green building engineer turned farmer who will spend the summer harvesting chard, root vegetables and herbs from the soil that supplies produce to around half a dozen neighborhood restaurants. And, it’s not just the plants that love the high-rise ecosystem, so do the crows. One autumn they ate all of his cover crop seeds. 

“We could not figure out for a couple weeks why they weren’t germinating until we came out one evening and realized that we had basically set a crow buffet,” Berini said.  “That’s one of the oddities.” 

Nick Berini, co-founder of Up Top Acres. Photo: Allison Deger

The farm is one of 13 green roof conversions run by Up Top Acres, Washington DC’s first and only commercial rooftop farm. Berini and co-founders Kathleen O’Keefe and Kristof Grina launched the company in 2014 out of an incubator in the affluent Georgetown neighborhood. The flagship location is in a former industrial area peppered with glassy condominiums and chic waterfront restaurants a few blocks away. Tucked between the city’s baseball stadium and a Navy yard. is 55 M St., a sweeping 15,000 square foot rooftop farm that also doubles as an event space and sometimes happy hour haunt. 

“I didn’t come to farming until later in life,” Berini said. “I grew up in Manhattan.” The first thing he planted, holy basil, an aromatic medicinal herb native to India. He started with a 20×20 ft. gardening plot in a community farm. 

“I studied engineering, I did building energy consulting. And at some point decided that saying sustainability didn’t really mean much if you couldn’t grow food or if you didn’t know how to grow food sustainably,” he reflected. “So I left the office and I started gardening and then farming full time.”

By 2017, the same year the Half St. farm opened, Up Top launched a CSA program. 

“We try to keep it reasonable for an individual who cooks a lot for a family who wants to use it for one or two meals a week,” Berini said. Members expect around seven different items a week. “People don’t like to get too much food that then they feel like they’re wasting.”

There are four pickup sites spread around DC and Maryland, “the closest one being the lobby of this building.”

Gardening in the sky. Photo: Allison Deger

Planting at an elevation of 120 ft. from ground level comes with it’s own subset of challenges and benefits. The perks are clear, bypassing soil pollution and access to space in an impacted urban environment where land is not only scarce, but expensive. Tall buildings have an added advantage of ample sunlight. Since the late 1800s the District restricted construction to no higher than the Capitol Dome. For Up Top, this means no afternoon shadows from skyscrapers to overcome. 

In early years Up Top grew watermelons. “There’s something really special about cracking open a purely ripe watermelon right off the vine. It is an incredible experience,” Berini explained. When it came time to buy seeds the following season, the team quickly realized leafy greens were more manageable. 

“It was extremely taxing,” Berini said. “Honestly just the logistics of hundreds of pounds of watermelon, moving up and down elevators.” 

The farms are not organic certified but they follow the principles of organic growing, as many other growers do given the complicated and often counterintuitive nature of organic certification. “We don’t use any pesticides or herbicides or inorganic fertilizers,” Berini said. “We do full crop rotation. No plant family will be planted in the same area, same zone of the farm, without at least two but ideally three or four years in between.”

“So basically, we’re asking different things of the soil every year instead of asking for the same nutrient over and over again,” he said. “It’s more sustainable for the  soil, healthier plants, more insect life.”

Rooftop blossoms. Photo: Allison Deger

Rotation is not as important for first-time growers using a planter box. A tip for aspiring planters: tomatoes are resilient and can grow in a variety of climates and conditions. But for more finicky plants susceptible to root rot, pay attention to the soil quality. He recommends dirt with less clay, which is more drainable.

“Our competitive advantage, let’s say, is basil. It is something that grows extremely well on the rooftop, and can be more complicated to grow in ground,” said Berini, gesturing towards tiny towers of shiny mint-colored leaves. “Up here we have our soil blend that drains really easily, perfectly to keep it lightweight. And we have incredible airflow and wind flow, obviously.”

But, “basil is sensitive to water and disease,” he added. Too much hydration causes water to pool around the roots and the leaves blanche, leaving them limp, pale—and worse—flavorless. “If you had your planter [box] and you packed it with a very clay-like water-holding soil, you might have the same struggles.”

For growing basil at home, something as simple as sticking the herb in an outdoor hanging basket typical for perennial flowers can be an easy way to remove excess water.

Pinching basil. Photo: Allison Deger

“There’s also a really important harvest technique for basil,” Berini underscored. It’s called “pinching.” In the mid-afternoon sun he hunched over a spire, plunking out of the top set of leaves, leaving the bottom to flourish. Left alone, the base can sprig out to the sides and expand the little thicket. 

“You’re essentially sculpting a basil bush that will eventually allow you to pick enough to make a pesto and not harm the plant,” he said. 

This approach allows for maximal yield without compromising the plant. Indeed growth can take place almost anywhere with a few key components: sunlight, water and soil that avoids retaining too much of the latter for more sensitive species. Yet it is titrating these ingredients and controlled harvest that will take a seed from the bag to germination, to the dinner plate, with consistency. 

Beyond this approach, any farmer from novice to pro should be ready to adjust to the wiles of nature. Even the 1015 Half St. farm, which is embanked by new construction, had to give up strawberries. Clever birds snagged the pulpy red fruit off the stolons before they had a chance to ripen.