At mid-September, with temperatures cooling significantly following several days of unseasonably hot weather at the start of the month, the pace of sugar development in Lodi grower Steve Felten’s wine grape vineyards had slowed.

“The heat caused fruit in some of our vineyards to sugar up pretty quickly, with more shriveling than normal,” he says. “Should temperatures remain on the cooler side, grapes not affected by the heat would have more time to ripen instead of just adding to sugar levels.”

The pace of harvest had also slowed. Earlier, his crews had been picking grapes in two or three vineyards at a time, but by the middle of September grapes were ready for harvesting just one vineyard at time.

The Felten family, fifth generation grape growers in the Lodi region, have 500 acres of wine grapes in Lodi’s Mokelumne River and Clement Foothills appellations. These include their own blocks of Old Vine Zinfandel, ranging in age from 40 to 120 years old, as well as other vineyards in the area that they manage. The grapes supply their Klinker Brick Winery. 

“The wines we’ve made so far this season have turned out pretty nice,” Felten says. “I think it will be a decent wine grape year, but not a banner one.”

He began harvesting mid-August, starting with two white varieties, Albarino and Grenache Blanc, and some Carignan, Grenache, Mouvedre, Syrah, and Zinfandel for rosé wines. At mid-September, his crews were continuing to pick Syrah and Zinfandel. He was expecting to finish this year’s harvest by mid-October, ending with Cabernet Sauvignon and Dolcetto.

“The Cabernet Sauvignon fruit looks really good,” Felten says. “I hope those grapes have enough time to sugar up before the weather turns against us. We shoot for a 26 ºBrix to 27 ºBrix to pick them. But, that means they’re hanging out there for quite a while. A lot of years we don’t reach that level before we need to pick them.”

Tonnage has been affected somewhat, overall, by the higher-than-normal amount of heat desiccation. Crews drop clusters with broken and shriveled berries before picking each block. However, his Zinfandel yields have been running slightly above average, which usually is around 4 tons to 5 tons per acre.

His vineyards faced very little pressure from insects this year, he says, and timely sulfur and fungicide treatments kept powdery mildew under control following light rains early in the season.

Still, this hasn’t been a completely trouble-free season. One of his Old Vine Zinfandel vineyards along the Mokelumne River stood in flood waters, which rose as high as the cordons, from February through May. “The vines grew out of it, and now look healthy,” he says, “but we won’t be harvesting them this year. We had to prune them really late and pruned them to get new fruit buds for next year.”

Felten, who picks about a third of his grapes with machines, says the number of workers available to harvest the grapes by hand keeps dwindling. “We could tell, when thinning shoots and pulling leaves, that the labor supply was tight. Still, the harvest seems to be moving along for everyone. But, the supply of workers gets tighter every year, and if that continues, the only way to survive as a grape growers will be incorporate more mechanized operations.”