Freeze: Local citrus growers worry about next year’s crop
An unusual lateseason freeze swept through the Central Valley Monday night and Tuesday morning causing temperatures in the citrus belt to dip into the low 20s for up to 5 hours in the coldest locations. The drastic swing in temperature will undoubtedly affect the area’s citrus crop, although the full extent of which won’t be known until Spring, California Citrus Mutual reported.
The current year citrus crop — navel oranges and mandarin varieties, specifically — are approximately 45-50 percent harvested, according to CCM. This late in the season the fruit remaining on the tree has a higher sugar content which can act as a natural defense against freeze damage.
With frost protection measures in place, temperatures stayed in the mid- to upper-20s for durations lasting as long as 5 hours. Generally, temperatures below 32 and 27 degrees can create an opportunity for damage in mandarin varieties and oranges, respectfully, CCM reported. Given the timing of this freeze event and the good size and sugar content of the crop at this point in the season, growers do not anticipate any damage.
However, the warmer temperatures and Spring-like conditions of the past several weeks have caused trees to start blooming 2-4 weeks earlier than usual, according to CCM. The quality and quantity of bloom is a direct indication of the size of next year’s crop and the quality of the fruit.
Drastic swings in temperature the Valley has recently experienced may cause early, fragile blooms to “drop,” which
could translate to a smaller crop for the 2018-19 season, CCM reported.
Young trees are especially susceptible to cold snaps during the bloom phase. In the coming days and weeks growers will start surveying groves for potential frost
burn on the new plant growth that is so vital going into the new season, according to CCM.
With the fate of next year’s crop of top concern, growers started implementing freeze protection measures early Monday morning
in anticipation for a cold night, possibly nights, ahead.
Growers report running water in the groves starting mid-morning on Monday in order to keep the orchard floor moist, CCM reported. Wind machines were also used to
elevate temperatures.
The warm orchard floor coupled with a decent inversion layer allowed wind machines to raise grove temperatures a critical 2-3 degrees. On average, wind machines were on for 8 hours, starting as early as 10
p.m. in some areas.
The coming days will reveal if damage was incurred. Growers are optimistic that if there is damage the trees will have ample time to bounce back and push out another set of blooms this Spring.