California avocado: end of season and orchard preparation for a rainier winter

California's avocado season is nearing its end, with the industry-adjusted crop reaching 332.02 million pounds as of September 20. Mexico remains the top supplier of imported Hass avocados as the market enters fall. For California growers, the focus is also on the trees and the upcoming season, with an increasing likelihood of a wetter winter.

California avocado shipments exceed weekly harvest

Growers harvested an adjusted 3.27 million pounds during the week ending September 20, an increase of approximately 14% from the previous week. Adjusted shipments totaled 5.93 million pounds , a decrease of nearly 10%. Shipments exceeded the new crop by 2.67 million pounds , reflecting that marketers continue to move existing fruit within the system.

Of the total reported, Hass accounted for 2.94 million pounds , while Lamb Hass contributed 196,940 pounds , and no new GEM crop was recorded. The adjusted season total reached 332.02 million pounds , exceeding the 330 million pound projection mentioned in last week's bulletin.

Mexico sustains the supply of Hass avocados to the United States

Imported Hass avocados totaled £57.30 million , down 6.9% from the previous week. Mexico accounted for £53.60 million (93.5% of the total), while Peru contributed £3.70 million . Mexican arrivals were down 4.5% from the previous week, and Peruvian arrivals declined from approximately £5.41 million.

Despite the lower weekly arrivals, imported inventory reported as of September 22 stood at 36.96 million pounds , a 4.9% increase compared to the previous week. Mexico accounted for 33.59 million pounds and Peru for 3.33 million . For the remaining Californian fruit, this situation reinforces the need for close coordination with marketers regarding harvest timing and sales opportunities. Volumes alone do not establish a price trend.

NOAA Forecast: Rainiest Winter Ever in Southern California

The NOAA seasonal forecast of September 17th favors above-normal rainfall in Southern California between October and December, with a wet signal intensifying toward winter. Along parts of the coast, the probability of above-normal rainfall reaches between 50% and 60% in the winter and early spring forecasts. The El Niño phenomenon is a key factor behind this projection.

These probabilities describe the chance of a rainier-than-usual season, not the exact amount of rainfall or the intensity of each storm. The forecast gives growers reasons to prepare now, while still monitoring local reports.

Rain can reduce the need for irrigation, but prolonged waterlogging deprives roots of oxygen and promotes Phytophthora root rot . Young trees, poorly drained blocks, and areas with a history of root problems require special attention. Even trees on slopes can suffer when repeated storms prevent the soil from draining and reoxygenating.

How to prevent Phytophthora in avocado orchards before the rains

• Check drainage: clean gutters, drains, and runoff paths. Identify low-lying areas and water accumulations around trunks. Prevent runoff from diseased areas from reaching healthy blocks.
  
  
• Adjust irrigation according to soil moisture: check sensors, valves, and for leaks. Reduce or pause irrigation when rainfall meets the trees' needs, and resume it based on moisture measured in the root zone.
  
  
• Manage mulch by layer: keep it away from trunks and tree crowns. Coarse mulch promotes root growth, but avoid excessive layers in slow-draining soils. Remove excess mulch if the soil remains saturated.
  
  
• Protect slopes and access roads: maintain managed vegetation cover to reduce erosion. Repair vulnerable drainage outlets and limit machinery traffic on wet soils.
  
  
• Review tree health and nutrition: inspect weak specimens and areas with root rot. September is within the UC's recommended window for foliar sampling; use results to guide nutrition.
  
  

After major storms, check for waterlogging, erosion, exposed roots, and blocked drains. Wilting in wet soil may indicate root damage; check conditions before adding water. Preventative drainage work now can help protect the trees and the crop developing through 2027.