The modern notion of merging the urban and the rural can be traced back to the visionary utopianist Ebenezer Howard, author of Garden Cities of To-morrow. To explain this novel concept, he liked to use the analogy of a marriage. The verdant countryside and the vibrant city would join together to become one, combining their incomplete virtues into a robust whole.

As nice as this may sound, anyone in a relationship knows that you still need your own personal identity. Some difference is good.

A few decades after Howard’s ideas had taken hold around the world, another equally passionate British planner wished the “garden city” had never been born. Taking stock of the now half-rural, half-urban modern English landscape, Thomas Sharp lamented,

The one age-long certainty, the antithesis of town and country, is already breaking down. Two diametrically opposed, dramatically contrasting, inevitable types of beauty are being displaced by one drab, revolting neutrality. Rural influences neutralize the town. Urban influences neutralize the country. In a few years all will be neutrality.

What Sharp was actually looking at was the tattered remains of Howard’s proposal, after the meticulous sense of scale, communitarian land ownership scheme, and green belt had been compromised away. All that remained was the awkward marriage acted out on individual homes in individual yards as far as the eye could see. Every suburban household was supposed to use their yard to grow their own food, at least in Howard’s vision, but it never really worked out that way.

Planning for the best of both worlds can leave you with little of either.

Dancing about architecture

Hayes Valley urban farm in San FranciscoProjects like Hayes Valley Farm, an urban agriculture education and research project located on San Francisco city-owned lots, are popping up all over America.Photo: EdibleOfficeAgriculture, no doubt, has a vital role to play in cities, and it can be done in a way that keeps the urban fabric intact. There’s no shame in thriving on the margins: the odd scraps of leftover land, rooftops, traffic islands and medians, the interiors of blocks, and, of course, the millions of back yards (and front yards) with a layer of grass waiting to be turned over. Azby Brown has written a beautiful description in The Atlantic of traditional Japanese urban farmers who have managed to fit a wide variety of produce into some serious density. Filling in these tucked-away spaces scattered throughout the city with green enriches food awareness and quality of life for entire communities. Wherever there’s constraint there’s innovation, and surely many deliciously ingenious opportunities are only awaiting discovery.

There’s also plenty more room on the margins of time. Jason King shows off an armful of what he calls “ephemeral urban gardens” on his blog Landscape+Urbanism.

“Landbanking” is the practice of holding on to vacant parcels, waiting for the market to make redevelopment possible. Often this empty space just gets co-opted into parking lots, which add little to a neighborhood and only encourage motoring behavior. What if these thousands of waiting parcels were farmed instead? Cities are always in flux, just like the changes in growing seasons. Maybe they could be taught to dance in rhythm.

Yet the potential to lose the “urban” in “urban farming” remains. Growing on these urban margins will honestly never produce enough to feed the city. The urge to stretch out into larger parcels and achieve some permanence in the face of redevelopment pressure is understandable, but we don’t want to get smart growth backward.

There’s nothing wrong with farmers breaking ground on the outskirts and taking the old farm-to-market road into town early Saturday morning. Achieving a 100-mile diet would be an amazing accomplishment. Fighting for a 10-mile diet misunderstands how regions work.