By the start of July, California’s raisin grape crop was developing about a week earlier than last year and as much as two weeks ahead of the usual pace. Thompson seedless berries began softening around the third week of June. That follows the start of veraison a week or two earlier in the Fiesta, Selma Pete and Zante Currant fields of the central San Joaquin Valley and home of the state’s raisin industry.
Judging by the bunch counts, raisin production this year should be down some from last year, reports Jerald Rebensdorf, president of Fresno Cooperative Raisin Growers, Inc. At the same time, a lighter crop load should mean less stress on the vines. That, plus the earlier maturity, should mean a good quality crop in terms of sugar levels, he adds.
Pressure from powdery mildew tended to vary this season from one vineyard to another, Rebensdorf notes. “Despite the really dry conditions, some fields, where growers didn’t follow a diligent spray program, had quite a bit of powdery mildew,” he says.
Meanwhile, 100-degree temperatures in mid-June increased the risk of foliage and fruit injury from sulfur burn where growers were using that material to help control the disease.
Growers without deep wells for irrigating their vineyards are facing the biggest production challenge this year. With deliveries of surface-water restricted drastically, if not curtailed altogether, some have been unable to irrigate their crop, according to Rebensdorf.
Also, water stress has left vineyards more vulnerable to damage from mites. “They had already begun showing up in pretty good number in mid-June,” he says. “Most growers have been spraying for them and will probably continue treating them until 30 days before the start of harvest.”
Rebensdorf, himself, grows organic Selma Pete and Thompson seedless grapes near Biola, Calif., where he’s served by the Fresno Irrigation District. In times of normal rainfall, he would be irrigating his vineyards with ditch water throughout the season, beginning in early March. Last year delivery of surface water didn’t begin until April.
At the start of this season, Rebensdorf was expecting to receive water for just 1½ months. However, his deliveries began in early June and now are scheduled to run through the end of July.
Typically, raisin growers stop irrigating their vineyards at the end of July or the first week of August. This year’s earlier-maturing crop should reduce, if only a little, some of the concerns about running out of water for this year’s crop, Rebensdorf notes.
Two of his wells went dry this spring. He was able to start pumping water again from one of the wells after lowering the bowls 40 feet. Rebensdorf is replacing the other well with water pumped from an adjacent field.
“A lot of growers are on waiting lists to get new wells drilled,” he says. “Probably at least 10 percent of our raisin growers have had wells go dry this season. In some cases, growers are providing water for neighbors, who have lost a well. Others continue to pump but, due to lower water levels, they’re not getting a full head.”
Following their large 2013 crop, raisin growers are hoping to get the same $1,650-per-ton price or more for their 2014 raisins this year as they did last year.
“Overall, domestic and export shipments through May 31 were up15 percent compared to a year ago,” Rebensdorf says. “The carry-in of raisins for the new marketing year beginning Aug. 1 is likely to be about 130,000 tons. That’s more than we’d like to see. But, that supply should satisfy demand until October, when the new crop comes in.”