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Recommended Harvest Criteria for Commercial WA-38 Storage in 2024

Prepared in August 2024. This document is reviewed and updated on an annual basis. by Ines Hanrahan, WTFRC, Carolina Torres, WSU

Printable pdf: 2024 WA38 Commercial Harvest Recommendations

General harvest criteria and procedures for all fruit

  • Starch Index (1-6 scale) minimum of 2.0
    • To qualify for packing, 90% of fruit in a lot must have reached a starch clearance of 4.5. Fruit picked at 2.0 starch clearance will take an average of six weeks in RA storage to reach the required clearance. (Example: Oct. 4 pick date + 6 weeks storage = Nov 20)
    • Fruit harvested below 2.0 starch clearing will not develop good flavor.
    • Fruit harvested at or above starch clearance of 3.5 may result in lower yields and/or packouts due to increased stem bowl cracking, bird damage, and development of fruit greasiness in the orchard and/or in storage.
  • Breaking background color
  • Decay management: Stem clipping recommended, pre- or postharvest fungicide, bin and room sanitation
  • Soluble solids concentration (°Brix) equal or higher than 11
  • Firmness (in lbs.) of 23 or below
  • Days after full bloom between 165–175
  • Ethylene action or synthesis inhibitors preharvest (ReTain, Harvista, ethephon etc.): not recommended.
  • DPA: not necessary (no superficial scald risk), but drench mixes with fungicide and DPA have not shown to cause phytotoxicity to date.

Use this guide in addition to the published marketing and quality standards for the 2024 crop year. First ship date for fruit produced in the 2024 crop year: November 25, 2024.


Young orchards (2 and 3- year old trees)

  • Fruit maturity development and rate of starch clearance in storage may be inconsistent.
  • Excessive greasiness may appear on the fruit preharvest or in storage and is not controlled with 1-MCP.
  • Heavy cropping of 2-year-old trees may stunt tree growth and/or may induce biennual bearing.
  • Fruit from young orchards is recommended to be sold in January/February

Mature orchards (4 year old trees and older)

  • Relatively consistent fruit maturity within trees should allow for one pick
  • Some fruit from oldest orchards should be considered to sell first due to even maturation pattern

Storage and Packing

  • Tasting fruit before packing and shipping is recommended to detect off-flavors.
  • Bitter taste is rare, and dissipates after several weeks in refrigerated air (RA).
  Storage Duration Starch Index 1-MCP recommended Background Color Additional Recommendations
Short RA 1-3 months 2-4.5 No breaking Fruit from orchards older than 3 years should be slated for early sales
RA 3 months 2-4.5 No breaking Refrigerated Air (RA): 32-34°F, >90% relative humidity (RH); ideal time to sell fruit from 2-3 year-old orchards
Short CA 4 months 2-4.5 No breaking Controlled Atmosphere (CA): 33°F, 1% CO2, 2% O2; ideal time to sell fruit from 2-3 year-old orchards
Mid CA 4-6 months 2-3.5 No breaking Controlled Atmosphere (CA): 33°F, 1% CO2, 2% O2
Long CA 6-12 months 2-3.5 Yes breaking Mature orchards only (year 4 after planting or older): 1-MCP application may reduce greasiness for fruit harvested at advanced maturity (3.5-4.5)

(Fruit destined for fruit stand sales: refer to PVM for the Farmgate Standards.)

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