In my childhood in Fatih, Istanbul, nearly every empty lot between the old houses held a "bostan," a small garden that supplied the neighborhood with fresh vegetables and fruit long before supermarkets did, and that everyone nearby took part in tending. I remember parents growing fruit there among hackberry trees, which were common in Istanbul’s old gardens.

As mischievous kids, whenever we snuck into the bostans to eat hackberries, the neighbors were not busy chasing us off. They were busy protecting the plants: "Do not step on the flowers. Do not pick the fruit before it is ripe,” they would say. I can still hear those warnings today.

Later we moved to Üsküdar, another neighborhood in Istanbul, right next to the bostan of Imrahor, and I can say without exaggeration that I grew up inside bostans. I still remember the smell of the soil, the sound of the gardener watering the plants at dawn, the humid summer air thick with the scent of lettuce and parsley. At the time, I had no idea how valuable this was. To me, the bostan was just an empty lot next to our house.

In truth, it was one of the last remnants of a centuries-old urban tradition. Istanbul’s bostans within the old city walls, especially those of Yedikule, had served as true production centers from the Byzantine era through the Ottoman period, feeding the city from within the shadow of its own walls.

This was exactly the point the late architect Turgut Cansever insisted on: the Ottoman city was built on a harmony between people, nature and the built environment. True urbanism did not exclude nature but wove it into the center of daily life. The bostan was the clearest expression of that harmony. Rereading Cansever today, I understand more clearly that the simple landscape of my childhood was, in fact, a deep philosophy made visible.

Why am I telling you this? Because a news story I read a few months ago took me straight back to the edge of the bostan of Imrahor. On the other side of the world, in the heart of Chicago, a strikingly familiar story was unfolding in an entirely different context.

Silence over Chicago

There is a particular kind of silence that settles over downtown Chicago's office towers these days. Elevators that once carried thousands of commuters now glide up mostly empty shafts, and floors once subdivided into cubicles sit dark. Anyone who has walked through the Loop, the city's historic business district, since the pandemic knows this feeling: a skyline still standing, but a city hollowed out from the inside.

And yet, on the 18th floor of a tower at 30 N. LaSalle St., something unexpected is growing. Farm Zero, a vertical farming operation founded by Russell Steinberg, has turned old office space into racks of microgreens, leafy greens, herbs and edible flowers grown under LED light. Where printers once hummed, there is now the quiet churn of irrigation, and where conference rooms once stood, there are now what Steinberg calls panic rooms and spas for plants, fully climate-controlled chambers. The company now sells its produce to nearby hospital systems, to workplace dining programs at companies like Jump Trading and Uber, and even to restaurants like Bazaar Meat and NoMI, all of it moving out of the same tower within hours.

I have to admit, reading this, I felt a strange contrast: on one side the open soil of the bostan of Imrahor, the sun, the seasonal scent; on the other a fully controlled production room under LED light. But thinking about it longer, the gap was not as wide as it first appeared. Both rest on the same instinct: let the city grow its own food within itself.

Steinberg himself is not, by training, a farmer. He came from the insurance advisory world, and his path began with an ordinary irritation, a friend's complaint about a rotten bell pepper, which sent him studying global food systems from Singapore to the Netherlands.

What made the idea concrete, though, was not the produce but the real estate. As Covid-19 emptied downtown offices, vacancy rates that stood around 14% before the pandemic climbed past 21% within a couple of years, and his friend, developer Lee Golub, posed the question that would define Farm Zero: what happens to all this obsolete office space? The answer was elegantly simple. Office towers already had what indoor farming needs: water lines, electrical capacity and heating, ventilation and air conditioning (HVAC) systems built for thousands of workers. Repurposing that infrastructure was not a leap; it was closer to a translation.

City in closed loop

For a century, the story of the modern city was one of importing food from far away and exporting waste just as far. Chicago's own history, as a rail hub built on shipping grain in from the prairie, is a monument to that logic. Farm Zero inverts it, much the way the bostans of Yedikule once let Istanbul meet its own needs from within its walls. Produce grown on LaSalle Street reaches a caterer or a hospital kitchen within 48 hours, sometimes just blocks from where it was harvested.

This is not, of course, a solution to every problem downtown Chicago faces. Vertical farming remains expensive to run, limited mostly to leafy greens, and Farm Zero itself is only now nearing its break-even point. As urban planning scholar Kheir Al-Kodmany points out, most of what such farms produce is still confined to leafy greens and microgreens, and while the technology works, its energy and operating costs remain genuinely in question.

But the deeper lesson is not really about tomatoes, cucumbers or kale. It is about what a city does with the buildings it no longer knows how to use. Vacant office towers are a form of civic memory, and as Cansever used to say, true urbanism does not exclude nature, but absorbs it. Perhaps today's cities are learning to refill their own emptiness with nature, with production, with life.

What cities choose to become

Steinberg says his dream is to see 50 million square feet of American office space converted into farms by 2050. The number may prove optimistic, but the instinct behind it is worth taking seriously.

The real lesson I take from this whole story is this: the modern city must be ready for its next great shock. Covid-19 showed that office towers can empty overnight, and given how quickly artificial intelligence is now reshaping white-collar work, living through a similar wave of emptying within the next decade is not a remote possibility. The real question is how we respond to that emptiness.

A city can leave its vacated floors to decay and wait for the next crisis, or it can learn, the way Farm Zero did, to quickly repurpose the water, electricity and climate systems already inside its buildings. I think the truly resilient city is not the one that predicts the shock in advance, but the one that can quickly make new sense of what it already has once the shock arrives.

Sometimes I think about this. Growing up at the edge of the bostan of Imrahor, I never imagined that the soil, the smell, the seasonal rhythm of that place would one day be spoken of as urban design philosophy. To me, it was simply a normal part of life. Seeing that same instinct resprout today in a Chicago skyscraper, in a completely different language but with the same essence, reminds me once again that Cansever was right: the moment a city cuts itself off from nature, it cuts itself off from itself. The elevator doors open, and instead of cubicles, vegetables are growing under artificial light. Perhaps that is not the strange part. Perhaps the strange part is that we forgot this for so long.