TONY LAU - [X]PRESS 2.0 AJ Adams, a regular volunteer at Hayes Valley Farm, moves manure.

A formerly empty lot in the heart of Hayes Valley was seemingly invisible for nearly 20 years to the people who live there -- a homeless encampment littered with vodka bottles, needles and tents that went up and down with the sun.

What was once an old freeway ramp is now a community garden that grows more than fava beans and tomatoes. The volunteers at the Hayes Valley Farm are growing the possibility of sustainable agriculture on a 2.2-acre lot ­-- in a city with more that 10,000 people per square mile.

In two of 22 Central Freeway land plots that were torn down in 2002, community activists said they cut the chain-link fence, cleaned up the used drug needles and killed the invasive ivy that choked the surrounding trees.

"It was a place where you may not want to be. There was a lot of crime, a lot of prostitution, a list of drug use and distribution," said Jay Rosenberg, co-director of Hayes Valley Farm. "Many people considered this a black spot in their memories and forgot about the vacant lot."

The farm sprouted like the Garden of Eden, with lush greens and the promise of fruit.
The farm, which opened Jan. 24, attracted droves of volunteers who completed its 18-month plan in six months. Plans included building soil, raising honeybees and forming compost pits, Rosenberg said.

Every week, the momentum grows. Since this experiment began, more than 3,000 volunteers put in over 8,000 hours of work, directors said.

"We've gotten almost three times as much done every day than we thought we were going to," Rosenberg said. "And you couldn't have honestly told me that there would be 150 people showing up every week."

The farm is funded by a $50,000 grant from Mayor Gavin Newsom's Executive Directive for a Healthy and Sustainable Food for San Francisco. Though the agricultural experiment is temporary, directors say it is spreading throughout the city by volunteers sowing the seeds for their own gardens at home.

The two lots are zoned for a residential development project that was halted in November 2009 in response to the real estate bust. The commercial and residential real estate developer for the project, Build, Inc., has a history of acquisitions in neighborhoods that are transitioning from affordable to expensive, according to their website.

Directors said that in two to five years, one parcel will be replaced by a 239-unit residential building, the other parcel will be developed in 12 to 18 years.

However, the farm is not confined to this chunk of land in central San Francisco.

"There is so much more happening and being produced here besides the soil," Rosenberg said. "So many people have learned about growing food, so many people have taken home little seedlings and raised them and started gardens in their yards, have attended our workshops, class, and our tours, and are looking at starting gardens
in their neighborhoods."

On a recent day, Margaretha Haughwout, a teacher at University of Santa Cruz who regularly volunteers at the Hayes Valley Farm, watered the vegetation surrounding the farm.

"There's an amazing vibe here, super healthy, really productive," Haughwout said. "This is really a teaching environment of what can be done."

On that same day, Christina Powers, 25, a student at City College of San Francisco, painted the first brush strokes of a chicken: yellow feathers on a mural lining the border of the farm.

"I feel this is crucial knowledge that a lot of people miss out on," Powers said. "I meet people here in the city who've never even been on a hike or touched the ground. So I hope this influences people to really get back to their roots, and maybe it'll become a trend."