A new law taking effect next week will mark another innovation for San Francisco: The city will be the first in the country to offer a financial incentive for urban farming.

Starting Sept. 8, owners of empty lots could save thousands of dollars a year in property taxes in exchange for allowing their land to be used for agriculture for five years or more.

It's part of the Urban Agriculture Incentive Zones Act, a state law spearheaded by local sustainable land-use advocates and state Assemblyman Phil Ting, D-San Francisco. The law encourages would-be urban farmers to turn trash-covered empty parcels into gardens with the assurance they won't be forced out after putting in a lot of time and money.

San Francisco will be the first to enact it because the Board of Supervisors has already passed the necessary local ordinance.

"It takes so much time to get a property in shape for farming, including building fertility in the soil and getting the infrastructure in place," said Caitlyn Galloway, who has run Little City Gardens on a three-quarter-acre rented lot in Mission Terrace for four years. "That's why this legislation is a step in the right direction."

Little City Gardens supplies produce to local restaurants and Bi-Rite Market and is one of the only commercial farms in San Francisco, but educational farms can also take advantage of the law. Cities with much more open space, such as Los Angeles and Sacramento, are closely watching what happens in San Francisco.

The bill was conceived as a way to help cities reduce blight and give residents more opportunities to grow food, even to raise livestock where health codes allow it.

Long waiting lists

"I have heard from literally hundreds of residents who would like to have the opportunity to farm, but the waiting lists for a lot of our community gardens are over two years long," said Board of Supervisors President David Chiu, who wrote the local legislation. "There is simply not enough space."

This law could change that.

To qualify, a lot must be at least one-tenth of an acre with no permanent dwellings. The property would be reassessed at the average price for irrigated farmland, currently $12,500 per acre.

For a comparison, the double lot that houses the 18th and Rhode Island Garden has been valued at around $2 million - although its current assessed value is lower since Aaron Roland has owned it for 17 years. Still, after he applies for the tax reduction, his annual $6,000 tax bill will drop significantly.

Roland offered use of the property to permaculture gardeners Kevin Bayuk and David Cody in 2008, who turned it into a demonstration garden that offers permaculture certification courses and hosts school groups. The garden's pathways and benches are open to the public, and volunteers harvest whatever food it produces for low-income residents.

Roland gets constant requests to sell the property, which has a view of downtown, but he wants to hold on to it partly in case his children want to build a house there one day.

"I also like what's going on now with it. It's this marvelous garden in the middle of the city that's growing food," he said. "Hopefully there are other people like me that eventually might want to do some development on their land but aren't in a big rush, and meanwhile want to let it be used for this kind of public purpose."

Karen Peteros hopes that Clear Channel, which owns the site of her educational bee farm, under a billboard in Visitacion Valley, decides to take advantage of the new tax break, which she estimates could reduce its current bill of around $21,000 a year to about $50.

A spot for bees created

San Francisco Bee Cause's lease on the property is $1 per year for four small lots. In 2012, Peteros and her co-founders and volunteers removed two pickup trucks full of trash from the site, put down soil, planted fruit trees and other bee-friendly crops, and established a bee colony.

They teach beekeeping at the volunteer-run farm, and get funding from the sales of the honey. But about a year after they started, Clear Channel decided to take back half of the parcels to use as a parking lot.

"They swept the lot clean of all the great soil we had been building," Peteros said. In the end, the company couldn't get permits to finish the project.

Under the new law, the five-year contract stays with the property even if it's sold, but if an owner wants to get out of it they can pay back taxes and interest. San Francisco's ordinance limits the tax savings of individual property owners to $25,000 per year; if the savings are higher, an official review is necessary. City officials in Sacramento, Fresno, San Jose and San Diego have expressed interest, but haven't yet passed the necessary local legislation.

Los Angeles is close to doing that, and Clare Fox of the Los Angeles Food Policy Council estimates there are 8,600 parcels within Los Angeles city limits that qualify.

"It's about food security and food access, but it's also about transforming blighted vacant places that are prone to illegal dumping into community places," she said.

"It's a way to beautify the neighborhood and stabilize real estate values. Plus, there are the environmental benefits. There's a whole slew of reasons why urban agriculture makes sense."