August and September in California is foodie heaven, a time when farmers markets and grocery stores overflow with plump berries, sweet nectarines and oozing figs.

But do you know what these fruits look like when they first sprout? Or how a farmer knows when they’re ready to be harvested?

Jewish National Fund, Bay Area Tribe and Birthright Israel want young adults to know the answers to these questions. On Sept. 21, they’ll bus dozens of people to an organic farm in Petaluma for an Eco-Farm Dinner, where visitors can tour County Line Harvest’s 26 acres and then dine on its crops.

“I call it the scratch and sniff tour,” said David Retsky, owner of the farm. “We’ll walk around, people can ask questions and touch the plants and the soil. Which is an experience for a lot of people — to see how a carrot grows, how a beet grows.”

Sherri Morr, regional director of JNF, came up with the idea of the Eco-Farm Dinner three years ago, around the same time Retsky, her nephew, started farming in Petaluma. She’s thrilled to finally put her idea on the calendar.

“I think it speaks to the Bay Area, it speaks to young adults, it speaks to the very beginnings of Israel, when everyone always thought of Jaffa oranges when they thought of Israel,” she said.

Retsky first became interested in agriculture after high school, when he spent a year in Israel harvesting fruits and vegetables on a kibbutz. He loved it.

“At the time, I didn’t really get it. But afterward, I realized it was really life-changing, to live like that,” he recalled.

When he returned to the United States, he found a job at an urban farm in Santa Barbara. After several years in Southern California and traveling the world, he settled in Petaluma and began farming. County Line grows salad greens, radishes, turnips, basil, onions, garlic, beets, carrots, chard, kale, tomatoes and strawberries, among other crops. Retsky sells directly to Bay Area restaurants and to consumers at farmers markets in the East Bay and North Bay.

“I think I’ve brought a bit of kibbutz to the farm,” he said. He hires interns each year, most of whom live on the farm. And though it’s in no way a commune [County Line is for-profit], “we all help one another,” he said.

The Sept. 21 event will not only include a farm tour and dinner, but also a conversation with two students from the Arava Institute for Environmental Studies in Israel. The speakers — an Israeli woman and a Palestinian man — will discuss how the environmental school also promotes dialogue and coexistence.

In addition to the tour and speakers, event coordinators say there also will be plenty of time for shmoozing during a wine and beer tasting and also during dinner.

Eli Raber, director of Bay Area Tribe, said he hopes the event builds community and inspires people to think more carefully about the food they eat and where it comes from.

“Being out in the field and talking to the farmer will make the dining experience so much richer,” he said. “I think it’s an experience that will stay with people.”

Tickets for the Eco-Farm Dinner are $40 (Birthright Israel alumni are eligible for a $10 discount) and include transportation to and from San Francisco, farm tour, beer and wine tasting and vegetarian meal. Buses depart at 4 p.m. Sept. 21 from Justin Herman Plaza. To purchase tickets or for more information, check www.jnf.org or call (415) 677-9600.