US California Farm Bureau Fed navel oranges-3

Citrus growers in California’s Central Valley have avoided their first dose of frost damage for the season, with sub-freezing temperatures failing to materialize as forecast on Monday evening (4 December).

While temperatures dropped to the low F30s in the early hours of the morning, frost protection is generally only needed at F27oand below for more cold-tolerant varieties like navels and lemons.

With approximately 85 per cent of the region’s navel orange, lemon, and mandarin crops still on the tree, growers breathed a collective sigh of relief, with many reporting the conditions were actually ideal given a run of mild weather to-date.

“At this point in the season, a gradual decrease in temperatures, rather than a sudden drop, will better enable a tree to adjust while promoting a steady maturation process of the fruit by improving color and increasing flavor,” advocacy body California Citrus Mutual (CCM) said in a statement. “Generally, last night's [Monday] temperature conditions were ideal for the area's citrus crop.”

For the less cold-tolerant mandarin varieties, growers did use wind machines for an average of 10 hours on Monday night, in combination with running water.

“The critical temperature for mandarins is generally F32o, however, growers will run wind machines at warmer temperatures early in the season to allow the trees to adjust,” CCM added.

Frost damage isn’t the primary concern for some Californian growers, with widespread wildfires in Ventura County having an impact on the local citrus industry, although the extent is unknown at this time.

“Reports indicate the area between Santa Paula and Ventura - a large citrus producing area in the region - was most significantly impacted,” CCM said. “Citrus Mutual continues to reach out to local growers as they evaluate the potential impact.”

The off-shore winds that have plagued Ventura County are forecasted to continue through until Thursday (7 December), so the worst is likely yet to come for the cities of Ventura, Santa Paula and Ojai.

The California Avocado Commission has put out an email of condolence to their growing community, implying there may have been losses of orchards.