As June began, raisin grower Kelly Duley’s 30 acres of Thompson Seedless vines near Fresno were about a week behind normal development, but were progressing nicely.
“They look beautiful, with a nice green color,” he says. “Thompson seedless love the cool, almost coastal-like temperatures we’ve had this spring. And, we haven’t seen a lot of mites.”
Duley is still waiting to see what, if any, impact a rare hailstorm in April might have on production this year. The damage appeared minor, mostly shredded leaves.
“I really won’t know how the crop was affected until I can see how the bunches form,” he says.
Duley has been making raisins for the past five years in a vineyard planted when horses were still providing the power for farming. Because limited space at the end of old vine rows and the age of wires and stakes rule out the use of machines, grapes are picked by hand and dried on individual paper trays
The wet, cool weather has pushed powdery mildew to the top of his disease threats this spring. To control it, Duley dusts vines with sulfur, applying it earlier, for a longer period and at higher rates than many growers. He starts treatments when vines have produced about 8 to 12 inches of new growth.
“A lot of growers don’t start until a week or two later, when new canes are about 2 feet long,” he says. “By that time, the mildew is already growing.”
Rather than the customary practice of applying about 10 to 12 pounds of sulfur per acre every 7 to 10 days, he applies it every 6 days at 16 to 20 pounds per acre. And he continues treating for about two weeks later in the season that a lot of growers.
“Many growers — often the ones with mildew all the time — say I’m wasting material this way,” Duley says. “With this approach, I spend about $500 to $1,000 a year on my 30 acres, and I’ve never had a mildew problem.”
Phomopsis has been a new concern for him this year. For the first time, he treated vineyards with a single application of copper to prevent the disease from gaining a foothold, applying it after the vines began producing new growth.
“The fungus was present in most vineyards in this area,” Duley says. “Everyone got their copper on before the rains came and stopped the disease from spreading.”
His sandy loam soils require more frequent irrigation than heavier soils. He draws water from wells for his drip system, and despite the wet weather, he started pumping as usual, around bud break, to keep the soil wet.
“We’ve had a lot of rain the past two months, but they’ve been small and haven’t penetrated past the first inch of soil,” he says.
Duley expects no problems getting enough water this year. Ponding basins in his area, which recharge his groundwater supplies, have been full for the past eight months.
The strong prices he received for his 2010 raisins enabled him to pay the $20 per ton cost of buying and spreading dry manure over his vineyard for the first time. The manure he uses — from cows not treated with bovine growth hormone — is required to meet guidelines for his organic production practices.
Duley applied the manure in December before he began pruning vines and plans to continue doing it annually. In keeping with organic standards, he applied just 2 to 3 tons of manure per acre. That compares to the typical 10 tons peracre rate used by many conventional growers.
When Duley bought his 30-acre raisin grape ranch in 2006, he didn’t intend to become a farmer. Instead, he was attracted by the farm’s large barn, which offered an affordable space to house the office and equipment for his painting business.
But not long after that the economy went into freefall, threatening survival of a business he had built over a lifetime.
Fortunately for him, raisin prices began moving up. He credits that to the work of the Raisin Bargaining Association (RBA), the non-profit grower cooperative that represents its members in annual price negotiations with packers.
“I would have gone bankrupt were it not for the higher prices negotiated by the RBA,” Duley says. “The prices I received for my grapes saved my painting business and enabled me to pay my bills during a difficult financial time.”
Today, Duley is serving his first term as an RBA director.
“I urge every independent grower who enjoyed the high price and free tonnage for their crop last year to join RBA,” he says. “It will help insure that raisin farming remains profitable by giving us more bargaining power with packers in determining the highest possible price for raisins sold on the open market.
“Also the more members the association has, the more seats it has on the Raisin Administrative Committee (RAC). This committee, which also includes packers, sets the reserve tonnage. It’s very important to keep raisin prices up so we don’t end up bulldozing more vineyards.”
The RAC has already set the price for 2011 raisins at $1,500 per ton, the same as last year, Duley says. Free tonnage is expected to be 90 percent to 100 percent. This is the amount of the field price growers receive upon delivery to the packer.