California Wine Grapes and the Historic Rains

Will the heavy rains and floods that went on from Christmas well into March harm the 2023 wine grape crop? Nope. 

Vineyard near Santa Rosa CA last January

One of the reasons the West Coast of North America, from British Columbia to Baja, Mexico, are able to grow premium wines is due to the lack of rain during the growing season. Precipitation while the vines are dormant isn't a problem. Grape vines bud out about March-April and the grapes picked around late August-early October.

Rain can do the most damage during flowering (late spring) and just before harvest though most of the late spring and summer there can be issues with mold. Rain just as the grapes are nearly ripe and are big and juicy is when extra water dilutes the juice, can split grapes, and easily lead to mold. 

Places like Europe and New Zealand can have issues with summer rains. Long periods of rain along with humidity can be damaging when the grapes are on the vine. 

In California typically the rainy time of the year is November through March with often an occasional short rainstorm a month or so on either side of those dates. Yes, some vineyards got flooded this year while they were sleeping. The vines are not harmed. The extra water after years of drought should help the crop size for 2023.