The slow developing sugar issue has not impacted the early low-sugar grapes wineries want for sparkling wine programs. However, it could if the weather remains cool and sugars do not develop as needed.

“We have been targeting some of our low sugar Thompsons at 16-18 Brix,” according to Nat DiBuduo, president of Allied Grape Growers, the state’s largest wine grape marketing cooperative.

The higher sugar programs for concentrate and dry white wine made from Thompsons are targeted at 20-21 Brix. “I believe the low sugar program grower is losing some production because the lower the sugar, the lower the weight of the bunches until they hit the optimum Brix and weight. But many growers are interested in getting started and getting the grapes off before they lose weight to mildew, rot and the threat of rain,” DiBuduo said.

The slow developing sugar issue could become “more challenging” as wineries demand more high sugars for wine and concentrate as the season progresses. This could create bottlenecks at the crushers with reds and whites at wineries at the same time.

While the Thompson crop is coming in larger than expected, early wine grapes like Grenache, Sauvignon Blanc and Chardonnay in the central Valley and Pinot Noir in the Clarksburg area and early grapes from the North Coast are coming in short.

“We are way behind on the North Coast, and some crops are off 25 percent or more,” DiBuduo said.

“Labor is becoming an issue everywhere, especially this week and next as the first (Sept. 20) raisin insurance deadline nears,” DiBuduo said. That is when hand-harvested grapes must be down on trays for raisin drying to collect insurance if it rains on them. The insurance deadline for machine-harvested raisins to be down is Sept. 25.

Machine harvest raisins must have cane cuts ahead of harvest. This requires big crews that are becoming hard to find, he said.

“The raisin guys are getting extra anxious because of the lack of labor and those hoping to mechanically harvest have got to get canes cut at least five days in advance of the harvester,” said DiBuduo. The labor shortage has been attributed partly to a prolonged apple harvest in Washington keeping workers there longer.

“Because of the large Thompson crop, some growers are having difficulty getting enough sugar to make quality raisins and get them harvested by the crop insurance deadline. They can pick later as sugars improve, but then you are really at risk. We are getting more calls from raisin growers (wanting to sell to wineries), and we hope to be able to handle a balanced sale so the raisin packers are satisfied and the wineries fulfill their need at the current prices, which have strengthened,” DiBuduo said.

Compounding the year is the fact it has been a heavy powdery mildew season. For the most part, growers have done a good job of controlling it. However, it is seldom a perfect job and missed powdery mildew pockets can lead to pre-harvest botrytis.  Those who did not do a good job at controlling mildew will be in even more trouble.

“Berries are splitting due to mildew pressure and growers are applying materials attempting to dry the rot in both raisin and wine grapes,” DiBuduo said.