That familiar old bank building, curving sensually around the corner of East Washington and Petaluma Boulevard in downtown Petaluma is a far cry from being a beacon of green design. The bright, sugar-cube Roman façade rises to incredible heights for a one-story building, and must be hell to heat.

But for the past year this commercial cast-off with 30-foot ceilings has embraced a new purpose that fits perfectly with the original aims of the Sonoma County National Bank it once housed: wealth accumulation. Only now, the treasured currency is seeds. Not just any seeds, but those of food plants that predate the self-enthronement of grocers and bio-engineers to decree for us what kind of tomato will be on the table.

Baker Creek Heirloom Seeds, the Midwestern company that opened a retail outlet in the 1920s-era bank building last year, has in just about four seasons brought back, placed in Amish-made retail racks, and made available to Bay Area gardeners a treasury of color, form and taste missing from mainstream markets for so long that some of us didn't even know it still existed. Sure, we can buy the same seeds online, but there is something powerful in this retail presence, something symbolically ingenious.

Walking into the seed bank for the first time, I was struck by the way in which the old building's details support the new business; at the transition zone between sidewalk and interior, the compressed-oval foyer is, oddly enough, shaped like a seed. And the extravagant ceiling height, intended originally to inspire reverence for the banking business, now helps emphasize sunshine and inspires a lofty confidence in the safekeeping of genetic wealth.

These recycled architectural statements fit the new paradigm of seed-wealth banking, precisely what 29-year-old owner Jere Gettle is about; his plan for preserving genetic wealth is to distribute it as far and wide as he can, both online and via this retail outlet aptly situated in the navel of the pure-food movement. And many folks in the movement, out there tilling the soil in their yards or in planters on their apartment decks, know that this new trend is essentially a grassroots (or, say, zucchini- and basil-roots) political movement that begins in the backyard and triumphs at the dining room.

From the unadulterated little bundles of DNA known as seeds come our past and our future—where the bland-tasting, grocery-store tomato breaks loose and emerges in its natural glory—tiny, mid-sized and giant gems ranging from lime-green and orange-yellow to pink and violet with as much variety in taste as well. I admired 179 varieties of tomatoes in the company's seed catalogue, a glossy guide that celebrates the garden success of customers as far away as Mr. Kelesoglu in Istanbul and as close as Petaluma Bounty Farm, less than a mile from the seed bank.

"People come here from all over the world," said Gwen Kilchherr, the staff horticulturalist I met on my visit. "We've had visitors from every state in the country and from every country you've ever heard of and some you've never heard of." Kilchherr has been with the seed bank since it opened last June. When I point to the hand-painted advertising on the 20-foot window glass, she says, "Oh, that's out of date." The sign claims more than 1,275 varieties of vegetables. "We have 1,450 now," Kilchherr says.

Something tells me that this seed man, Gettle, must be getting on the nerves of the bio-engineering people and their lawyers. If only he weren't so damn successful, they could ignore him and the pure-food movement that continues to grow. Baker Creek is reportedly supplying schools, orphanages and prisons with seeds, about $100,000 worth this year, making Gettle something of a Johnny Food-Seed figure, emerging at the eleventh hour to oppose the Frankenfood industry head-on.

Monsanto is busy narrowing options, promoting monoculture and controlling ownership of engineered plants, while Gettle is busy spreading safer and cheaper options, expanding biodiversity and encouraging gardeners to save their seeds. His Petaluma retail presence gives an old bank new purpose; like a seed, it houses future growth for a more precious form of wealth.

Baker Creek Heirloom Seeds, 199 Petaluma Blvd. N., Petaluma. www.rareseeds.com.

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