Submitted by Chris Ritcey on Wed, 05/18/2011 - 17:00
Are May rains a problem in the vineyard.
We just finished a pretty significant 2-3 day rainstorm here in Petaluma. You might wonder what effect this late rain has on the farm. In a dry year, any replensihing of the groundwater, where our farm's water comes from, is welcome. But this year, as the past few, have given us normal rainfall. So groundwater is my part of Sonoma County is not an issue.
Rain can cause a late flush of grass to grow. Generally, this is not good because the farm has been mowed as fire protection, and now a good portion will have to be done again. Takes time and uses fosil fuels to run the tractor.
Rain can cause mildew in the vineyard. Generally, the vines are already being protected against this, but is can be a concern if it remains wet for too long. Our vineyard will get a dusting of sulpher in a few days, as insurance. And if the grapes are in bloom, the rain can prevent the formation of the grapes in the cluster. The result is lower yields and unevenly sized berries in the clusters. Uneven sizes can mean uneven ripening. Lucky for us, the grapes are not in bloom here in Petaluma, But that may not be true in some other parts of the state and county.
So far, we are on track for a good year.