News and Stories

FROM THE FIELDS: Heat Wave in Western Growing Regions

March 25, 2015


Markon First Crop (MFC) Green Leaf, Iceberg, and Romaine Lettuces are limited; Markon Best Available is being substituted. MFC Strawberries are currently available, but may become limited in the coming days.


Weather forecasts are calling for above-normal temperatures in all major Arizona and California growing regions over the next several days, perhaps longer. The most significant rise in temperatures will be experienced in the desert regions of Yuma, Arizona and Coachella, California where highs will reach the mid- to upper 90s beginning tomorrow and continuing through the first week of April.


The Huron, California region will see highs in the mid-80s to low 90s for several days. Salinas, Santa Maria, and Oxnard, California are expecting mid- to upper 80s through Saturday, March 28 before returning to the mid-70s.


Heat-related quality issues are already being reported by Markon inspectors in iceberg and leaf lettuce supplies from the desert region. All Western growing regions can expect to see a decline in quality and/or shelf-life due to this latest heat spike. The list below and attached pictures are examples of heat-related quality issues that are currently present or are expected to develop or worsen in the coming days.



  • Dehydration
  • Hollow core
  • Increased mildew pressure
  • Shortened shelf-life


Commodity and Value-Added Lettuce & Tender Leaf Items

  • Dehydration
  • Elevated insect pressure
  • Growth cracking
  • Higher respiration rates
  • Inconsistent texture/chunks
  • Increased mildew pressure
  • Internal burn
  • Rib blight, varnish, or decay
  • Shortened shelf-life
  • Sunburn



  • Bruising/bleeding
  • Decreased size
  • Over-ripe fruit
  • Shortened shelf-life
  • Soft texture


Markon inspectors are monitoring supplies in all major transitional growing regions and will continue to work with suppliers to select the best available product for Markon orders. Maintaining the cold chain throughout distribution is a critical part of maximizing the quality and shelf-life of perishable produce items, particularly during periods of volatile weather and transition from one growing region to another, which are both currently taking place. Ordering for quick turns is also recommended.


Please contact your Markon customer service representative for more information.


John Galvez

Quality Assurance


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