“It’s magic dirt,” a grower representative once told Derric Kirschenmann of the soil in which he grows table grapes near Shafter, Calif. — it’s not too heavy, not too sandy for the several different varieties of table grapes, including 60-year-old Thompson Seedless vines that continue to produce well, despite their age.

The Kirschenmann family’s Kern County roots trace back to the early 1920s, before the Dust Bowl pushed Plains states migrants west to farm and work the oil fields of the south San Joaquin Valley.

Derric is the fourth generation to farm the area. His father, Kenny, and uncle, Mark, are the sons of Leroy Kirschenmann, who got his start with potatoes. Leroy’s father, Adolf, was once the mayor of Shafter.

Kirschenmann Farms now grows table grapes, Pima cotton, almonds, silage corn, alfalfa, and carrots. Until recently the family also grew the potatoes that Derric’s great-grandfather and other family members began growing about 100 years ago.

In addition to producing their own crops, the Kirschenmann family has a custom farm management company based in Shafter. They do custom spraying, harvesting, GPS field layout, field management, certified nitrogen management — and pretty much anything else needed to produce crops in a region where some of the soil is quite sandy.

HIGHLY PRODUCTIVE GRAPES

About a decade ago, when Derric began marketing his grapes through King Fresh at Kingsburg, Calif., a grower rep suggested replacing older vines with higher-producing ones. “Just wait,” Derric said. “Let’s see what happens.”

What happened amazed the grower rep, and pleased Derric. The Flame variety, a red seedless grape, produced 1,800 boxes per acre, and his old Thompson seedless, a green variety, continued pushing out 1,200 boxes per acre.

“I’ve always told my dad that the day we don’t make 1,000 boxes is the day we pull them — yet we continue to make over 1,000 boxes on the ranch.” Growing good table grapes varies according to soil and water conditions, he says, and can also vary with “the amount of patience you have.”

Three years ago, he planted a few acres of the Shasta almond variety to experiment with the new self-fertile variety by Burchell Nursery. The idea is to see if they can move away from having to rent bees to produce almonds — a cost that’s increasing across the state as pollination services continue to rise, and the competition for bees increases as farmers continue planting more almonds.

LABOR COSTS MOUNTING

Derric begins each year pruning vines back to the cordon. Table grape vines are pruned differently than wine grape varieties. He wants to have green grape varieties picked by July 1, but that doesn’t always happen. He likes the marketing window he has for his grapes. There is typically not an overabundance of grapes on the market during his summer harvest, which can bring him a better price per box.

Labor continues to be a big issue as the cost of hiring that labor in California continues to rise. In January, he’ll spend about $1,000 per acre on pruning vines – a cost that will only continue to rise each year as California’s minimum wage increases.

“I don’t have a problem getting labor or keeping it,” Derric says. “I have a good labor contractor.”

Still, the cost of hiring that labor continues to rise, which he says “is a tough deal” because it is difficult to pass along the rising cost of business through higher per box prices for his grapes.

“There’s got to come a time when our brokers say, ‘This is what it’s worth, and what you need to pay,’” he says in defense of the need for higher grape prices. “The fear is that the broker or the farmer will get stuck with product that can’t be sold.”

As labor challenges in California increase, he says he still seeks ways to build efficiencies into his operations. Vines are irrigated by drip systems, and some of the berry thinning that was once done by hand can now be accomplished with sprays.

CONVERTED TO WINE

They also recently converted some Thompson seedless grapes from table to wine grape sales when yields dipped below Kirschenmann’s 1,000-box threshold. The result of that move was the ability to mechanically prune and harvest vines that made 12 tons of grapes per acre last year for wine markets.

Derric says he can produce table grapes within two years of planting a new vineyard, but prefers to take four years before his first harvest in order to give developing vines an opportunity to produce a good trunk. He’ll treat his wine grapes similarly.

He talks about harvest timing and the flavor of various table grape varieties: He understands that consumers who have a bad experience in the store by purchasing sour or off-flavor grapes may not buy grapes again – at least for a short period.

He also thinks consumers aren’t educated about grapes: that markets want year-round supplies, but must source those grapes from South and Central America during times in the season when California is not producing them. Grape harvest begins in Mexico in May, then quickly moves north through California, beginning first in the Coachella Valley, and eventually moving to the San Joaquin Valley. U.S. harvest will wind down by November, when Chile and Peru start harvesting their crops.

PRODUCER EXCHANGE

Each year Derric and family host a tour of visiting cotton farmers from across the cotton belt as part of the National Cotton Council’s Producer Information Exchange, or P.I.E. Tour. The summer trek to California allows farmers from other parts of the country to see firsthand what farmers like him do to produce fruit, fiber, and nuts in the state’s rich soil.

Derric participated in the tour several years ago, visiting farms in Georgia and north Florida, and says he enjoys giving back to the National Cotton Council because he appreciates how much he got from it.

“My goal is to make sure participants on the P.I.E. Tour understand what’s involved in producing the grapes they buy in the store,” he says, noting that nearly nothing is off-topic to the visiting farmers when he explains the different varieties, markets, margins, labor, and the pest anddisease issues California table grape growers face.

Mildew pressure during the early summer harvest can be high because of high humidity. He says he tends not to have pressure from the glassy-winged sharpshooter, a pest blamed for spreading Pierce’s Disease in vineyards. Because of the mildew issues, he continues to evaluate which varieties he grows, since some require double the number of fungicide sprays as other varieties. Red varieties tend to withstand mildew better than green varieties. “I don’t know why that is,” he says.

STATE OF THE INDUSTRY

Derric remains optimistic about the California table grape industry as new varieties are developed that are sweeter and popular with consumers. Still, he says, the cost structure of table grapes will remain high because of the manual labor needed to prune and harvest the crop.

“American grapes are probably better than you’ll get elsewhere. The problem is that consumers might see grapes at Thanksgiving and Christmas and buy them, not knowing they probably sat on a boat for 20 days. I’m not saying that any of this is bad fruit — but the timing is important. And I still think California fruit is the best fruit.”

He says he’d like to see the California Table Grape Commission do more to promote table grapes to consumers. “I think they’re a bit behind the eight ball when it comes to promoting grapes.”