LinkedIn icon The word "in". Email icon An envelope. It indicates the ability to send an email.

Sean Gallup/Getty Images

Once, the roof was silver tar, sticky and blinding in the summer heat like a melting spaceship.

Now, it’s a green oasis three stories above the ground.

Annie Novak hunches over rows of crops, harvesting chard and arugula as she looks out over empty rooftops towards the Chrysler Building, the East River, and the water towers and smokestacks of derelict industrial plants.

Her garden, Eagle Street Rooftop Farm, is a 6,000-square-foot for-profit operation atop a soundstage in Greenpoint, Brooklyn.

Novak’s model—the sprawling, elevated farm with dozens of varieties of produce, plus bees, chickens, and rabbits—won’t work for everyone. But no matter your housing situation, there’s something any urban dweller can grow. Two experts told CityLab how to settle on the right crop (and keep it alive).

Consider sun and space. Most edible plants thrive in full sun, meaning 6 to 8 hours a day, says Novak. If your building is a little less drenched, you can still try herbs such as basil, thyme, or sage.

They’ll even hold their own in small containers on your window sill, if you don’t have outdoor access. (Cold drafts, though, will work against you.) If you’ve got a small patio or terrace, try greens such as collards, chard, or lettuce. Plants with fruit—including dwarf varieties of trees, as well as berries and tomatoes—are the most demanding.

Novak cautions against going rogue and dragging plants and pots out onto the roof or balcony without making sure it’s structurally sound, and that you have legal access.

Check your local building codes and use common sense. “If you have to crawl out a window and up a fire escape, and no one’s ever up there except for you, that’s not a great sign,” she says. Novak’s new book, The Rooftop Growing Guide: How to Transform Your Roof Into a Vegetable Garden or Farm, has lots of tips for people who can forge ahead.

Don’t start a little farm on your balcony unless you’re sure it can hold the weight. Anna M. Stevenson/Flickr

Choose plants with a big yield for little effort. K.Ruby Blume, the founder of the Institute of Urban Homesteading in Oakland, California, recommends broadcasting lettuce or mesclun seeds.

Microgreens are a good choice because you can harvest them quickly and often. “You can eat arugula even if it’s an inch-and-a-half tall,” says Novak.

Another approach would be to prioritize rarity. Novak planted borage flowers because she had trouble finding them at markets. (The little blue petals taste a bit like cucumbers; Novak uses them as cocktail garnishes.)

Many plants for sale at big-box stores or bodegas have been shipped across the country. They might not be the varieties best suited to growing in your area. Blume suggests buying plants from your local nursery, where an expert can help you decide what will have the best chance of success.

Start small. On her urban lot, about 1/10 of an acre in Oakland, Blume tends to fruit trees, berries, grape vines, hops, and a vegetable garden, and raises pigeons, chickens, and other animals. It’s quite a spread.

Then again, she has temperate weather, plenty of space, and 30 years of experience. Blume says that novice urban gardeners have a tendency to try to tackle too much. “Don’t imagine that you can plant everything at once and have it go well,” she says. Start with one or two plants this year, and see how it goes.

Eagle Street Rooftop Farm in Brooklyn, New York. Inhabitat/Flickr

Select the right container. Blume points out that plants in the ground have room to spread their roots many feet wide.

They’re constrained by the diameter of containers. Admittedly, it’s easiest for car-less consumers to opt for a smaller container that’s easier to cart home on public transit, Novak says.

But the snug fit won’t do the vegetables any favors.

Herbs have shallow roots and can handle being tucked in to a windowbox.

But for produce such as zucchini, tomatoes, and eggplants, Blume recommends a 15-gallon container. “The more dirt and space you can give a plant, the better it’s going to do,” Blume says. (Melons and squashes will benefit from a trellis, too.)

A sturdy container is a good choice for a balcony, where a flimsier one could blow over in a gust of wind. And bigger containers are often a little better at retaining moisture, which will be handy during the season’s hottest days.

Regardless of the size of the container, you’ll want to add compost or organic fertilizer throughout the growing season. That’s because potting soil is a bit of a misnomer. Most mixes designed for containers are a combination of peat moss and coconut coir; they drain well, helping to prevent the roots from rotting, but on their own, they won’t fuel optimal growth. “At a certain point in the season, the plants will tap out without supportive nutrients,” says Novak. “Compost is a quick and dirty way to top them off a little bit.”

Get involved in other ways. Maybe you’ve tried to coax vegetables to grow and have nothing to show for it but a few wilted, spindly stems. It’s possible that the effort outweighs the payoff—but that doesn’t mean that your affair with fresh food has to be over. “If what you really want is to be involved in your food system,” says Blume, “there are better ways.”

She suggests volunteering at a food bank or soup kitchen, or seeing if your local CSA, community garden, or small-scale farm needs an extra set of hands. Volunteers keep those places going strong, she says. “Lots of amazing organic farms would love people to come out one Saturday a month and weed in exchange for food.”

NOW WATCH: Popular Videos from Insider Inc.