MSU Extension Apples

The information below includes predicted dates for peak harvest. Actual harvest dates may begin before and extend after these dates, and it is likely to vary based on specific location and conditions. This information is intended to be used by commercial growers to start planning harvest management. Interpretation is necessary for marketing purposes and fruit may be available in retail locations at different times.

The predicted harvest dates for all Michigan State University Enviroweather Stations are now available online and can be determined using the Apple Maturity Model on the Enviroweather Website. These models for McIntosh, Jonathan and Red Delicious calculate predict harvest dates based on full bloom date and the temperatures in the 30 days after bloom.

Most varieties are predicted to harvest 10 or more days earlier than normal due to warmer than normal conditions during early spring pushing bloom earlier and warm temperatures for the month following bloom. Harvest dates may need to be adjusted as we get closer to harvest.

Crop load. Blocks with light croploads will mature 3 or 4 days sooner than the predicted harvest dates while heavy crop loads will mature 7 days later than the predicted dates.

Conditions during August and September will also affect harvest dates. If hot stressful weather occurs in August or September, apple maturity will be advanced, especially in early to mid-ripening cultivars.

Stop-drop materials. ReTain application should be applied 21 to 28 DBH (days before harvest), depending on the variety and season. Harvista can be applied 3 to 7 DBH.

The tables below list the normal and predicted harvest dates for varieties across the state. Table 1 lists the predicted harvest dates for locations across the state of Michigan for 2024. Table 2 lists this year’s predictions compared to normal and last year.

*Dates indicated by model, not by actual observation.

* - is days earlier, + is days later