Getting your produce from a rooftop garden in your own city has its advantages. For one thing, the freshness factor is maximized, without all the untold hours that your food spends in a dank truck puttering along the highway en route from some rural farm to your local market.

Also: the chili peppers — wow! So spicy!

"Here is a fun fact: peppers grow exceptionally well in cities," says Anastasia Plakias, co-founder of Brooklyn Grange, which operates the world's largest rooftop farms. "Hot peppers, that is," she clarifies, "because they require sustained warm temperatures to produce capsaicin." Plakias is referring, of course, to the active chemical that gives chili peppers their piquancy, or "heat." In other words: you need heat to make "heat," and America's concrete jungles attract plenty of that New York City, especially.

"Of course, cities, like New York, experience what’s known as 'urban heat island effect,' the effect by which all sunlight is absorbed during the day, and then emitted at night," says Plakias, sounding ever more like a scientist than a simple farmer. "And, of course, you’ve got eight million people using ACs and running fans at night. So, what you're left with is, those heat wave days, when you think, 'Oh, I’ll go down tonight when it gets dark and sit on the stoop and catch a breeze.' And, you go outside and it’s just as hot as it was at noon. Meanwhile, our neighbors in Westchester are cooling their heels on their porches with average seven-degree cooler temperatures."

Indeed, the Westchester crowd might enjoy the milder summer weather. (And, lower energy costs. And, less air pollution. And, reduced risk of heat-related illness. And, better water quality. And, all the other supposed perks of living outside the "heat island.") But, their peppers won't be nearly as good. Or, so the theory goes.

"Their peppers are not gonna pass muster in a pepper taste-test with our peppers," Plakias says proudly. (Brooklyn Grange, incidentally, produces jalapeño, habanero, South American ají dulce and Hungarian wax peppers, among others, she says.)

To be fair, a professional urban gardener like Plakias is naturally biased when it comes to the quality of city-grown produce. But don't take her word for it.

Michael Mazourek, an assistant professor at Cornell University's College of Agriculture and Life Sciences and noted pepper researcher, says there's some truth to Plakias' city-centric pepper pride. "Peppers are indeed hotter when they are grown in hot, dry conditions," Mazourek tells Food Republic in an email. "And it's true that cities tend to be warmer than the countryside, but I would tend to credit the pavement and buildings." He adds, "I wonder what folks from New Mexico would say…"

Chef Eric Korsh has also become a big believer in Big City pepper production. Anecdotally, anyway, he's noticed a substantial difference since taking over the kitchen at New York's North End Grill, which benefits from a sizeable rooftop garden, located high above its Battery Park City location.

Years ago, Korsh ran a restaurant in notoriously sweltering Sonoma County, California, where he also grew chili peppers, including two types (pimiento and Carmen) that he presently grows at North End, as well.

Comparatively speaking, it's no contest. "The chilis are doing better on the roof at North End than they did in direct sunlight on the ground in Sonoma County," Korsh says. "It is kind of amazing. They look better, they're growing faster, they're ripening faster. I'm getting more of them per plant….It's like night and day."

And, Korsh points out, "we haven't really had a hot summer."

Too bad, then, that North End wasn't around back in 2010. New York's hottest summer on record would have made for one heck of a harvest.