SAN FRANCISCO In this city of hills, stairways are more than the shortest point between two altitudes.
Some are famously steep, twisty, narrow or meandering places for hiking, running, gawking at views, loitering, proposing. But now, among more than 600 sets of stairs, there is something new the first edible, sustainable garden steps at Bengal Alley.
"I don't even really like kale," said Kay Curry, standing in her kitchen cooking lunch for volunteers who recently had come to work on the stairway, which runs by her house and was bulging with the crinkly green vegetable.
Curry certainly never set out to create a permaculture showcase in her backyard, which was previously, she said, "a laboratory of what doesn't grow here."
About 20 years ago, she and her husband, Fred, moved into their house at the top of Bengal Alley in the western portion of the city. The stairway was worn out but still walkable. It was even included in guidebooks to the city's staircases.
But the cobblestones at the top needed attention, and the concrete stairs at the bottom were cracked. Weeds were crowding in everywhere. A rainstorm in 2004 set off a mudslide that inundated the lower section and the street below.
Then came complaints about safety because of the unwieldy steps as well as break-ins associated with the increasingly dilapidated alley. The city closed it down.
Homeowners along the alley didn't mind the closure, said Curry. But others in the neighborhood wanted it repaired so they could reach the top of nearby Mount Davidson or the bus route at the bottom of the hill faster.
A city agency sent the homeowners a notice ordering them to fix the alley, which is a public right of way through their property.
Kay Curry, who became a leader of the newly formed Households Adjacent to Bengal Alley, met with city officials. They offered suggestions but no solutions, she said. The homeowners decided they wanted to fix the stairway as a group but weren't sure how to proceed.
Then the Currys enrolled in a permaculture class. It helped them realize the possibilities and complexities, including soil quality, water retention and climate variations.
So the group hired a consultant who was a permaculture designer, a contractor with experience building on steep hillsides. and a local organization that knew how to create sustainable gardens.
They received a small grant for cobblestone repairs and footed the rest of the bill more than $100,000 for what they now consider their own small stairtopia, a walkway lined with edible plants and fruit trees in a terrain designed to catch and store water for irrigation.
"Why build this?" said Felipe Santander of Integrated Habitats, the ecological design studio that worked on Bengal Alley. "The challenge. It's not a common space to turn into a garden or a public educational site, but stairways are about connection."
They are also about taking time to see the environment in detail, says the city's stairway aficionado Adah Bakalinsky, author of "Stairway Walks in San Francisco."
At 90, Bakalinsky still climbs daily, sometimes leading schoolchildren. A stairway that teaches them local ecology is a welcome addition, she said.
"There are so many differences (in stairways) depending on who lives there and how connected they feel as neighbors and how they feel about keeping the area beautiful and lively," she said. "It's a wonderful focal point."
In her years of study, Bakalinsky has learned that there is a science to a good staircase. The French figured out the ideal technical proportion of steps in the 17th century, but there are always tricky issues of what will grow in each of San Francisco's microclimates and what will appeal to each neighborhood.
"You have to be careful because plants grow differently here than in Potrero Hill or the Mission," said Katy Broker-Bullock of Integrated Habitats. "The ocean breeze whips up this alley."
On the first community volunteer day others will be held the first Saturday of every month Broker-Bullock and Santander supervised workers who were sweeping, weeding and planting. A stand at the bottom of the hill sold products from the stairway edible calendula flowers and comfrey salve.
"You can just eat these," said Broker-Bullock, snapping off the leaf of a fava bean plant and popping it in her mouth as she walked up the stairs.
She pointed out red Russian kale, strawberry plants and French sorrel. The pathway underfoot was made from recycled pavement.
Further up were lemon verbena, red clover, parsley and oregano as well as guava bushes and loquat and apricot trees. Two irrigation valves provide the minimum amount of outside water necessary.
A group of interns from Supervisor Norman Yee's office came to volunteer. They had no idea what most of the plants were.
Kale? No one had ever seen it in the wild.
"I tried kale chips once," said Abigail Solaiman, a high school junior.
She and other visitors were encouraged to taste as they walked. The garden's curators expect more problems from gophers than people.
"If people do help themselves, that's part of the education, part of developing a relationship with the site," said Santander.
"As with everything," he added, "there is an element of trust."
Katherine Seligman is a San Francisco-based freelance writer.