Many growers were thankful that California received some much-needed rain. However, the early-season storm system that came through could create issues for raisin grapes. Technical Viticulturist for Sun-Maid Growers, Steve Vasquez said vineyards are fairly damp, but not saturated.
“So, guys who have raisins on trays, or continuous trays that are drier, will fare better,” said Vasquez. “Greener grapes or grapes that are in between fresh and dry, will have the potential for some damage as a result of that free moisture, which encourages mold growth and insect damage.”
While Northern California received the majority of rain, areas of Southern California also had several inches of rain. Parts of San Luis Obispo County received as much as 2.04 inches, while Santa Maria recorded 1.71 inches of rain on Monday. The storm also brought intermittent rainfall to many areas of the Central Valley. With the storm dissipating, the forecast indicates that the rain is likely over for most of California. Vasquez said they will need warm weather and some wind to help dry things out and reduce the likelihood of damage.
Depending on the maturity level of the fruit, growers have some options for mitigating any negative impacts from the rain. Vasquez said that if the raisin grapes are close to being dry a grower can pick them up and take them to the processor. Most processors can address the free moisture in the fruit with driers. Growers with less mature fruit could have some decisions to make.
“If they’ve got greener or wetter fruit, it’s a bit of a challenge. That fruit basically has to stay out there unless a grower really wants to pick it up and send it to a dehydrator,” Vasquez noted. “There’s some added cost that goes along with that and there’s potential for additional damages. You’ve got partially dried fruit going into bins, and they typically have to be half-bins. So, a grower’s going to need a whole lot more bins if that is the case.”