MSU Extension

General apple harvest comments

Harvest of most summer apple varieties is now complete. Growers are looking to begin harvest of early maturing strains of Gala, the first of the fall apple varieties, late this weekend or early next week. Honeycrisp, McIntosh and Early Fiji were also tested this week to determine their maturity. All three of these are a week or more away from being ready for harvest. Growers who have had plenty of moisture this season are seeing large fruit size as well as bitter pit and some sun scald issues. For growers who have had a dry season, fruit size is a challenge for many varieties. Fruit color is fair to good, but color seems to have been lost over the last week or so.

Overall, there is a wider range of maturity within blocks this season compared to most seasons. This maturity variability exists from tree-to-tree and in some varieties from branch-to-branch. This will make harvest challenging. Harvest labor is adequate for some farms and running short for others as we begin to ramp up apple harvest.

This is the first Southeast Michigan Apple Harvest Report for the season. Statewide reports will be available on the Michigan State University Extension Apple maturity program and reports page every week.

Apple Maturity in southeast Michigan for apples harvested on Sept. 3.

Individual variety results

Gala were sampled for the first week of the fall harvest season. Growers are looking to begin harvest soon, late in the weekend or early next week, on the early maturing strains of Gala. Fruit size is a problem in many Gala blocks and some growers are hoping for a good final swell in Gala in the next week. I have not seen any stem end cracking on Gala yet this season.

Color is generally good in Gala this season, averaging 81 percent. Early maturing strains are showing high levels of internal ethylene of greater than 0.2 parts per million (ppm). The fruit remains firm averaging 21.8 pounds, but there is a wide range of firmness depending on the strain. The starch index averaged 2.3, which is on the low side of being mature and is the prime reason I am suggesting Galas are not ready for harvest quite yet.

McIntosh were sampled for the first week of the season and are still eating green. Some blocks had high percentages of fruit with internal ethylene levels greater than 0.2 ppm; others tested no fruit above the 0.2 ppm level. The color is generally poor in McIntosh at this time, averaging 51 percent, and the firmness remains excellent at 16.7 pounds. The starch removal is fine at 3.1; recall that McIntosh need to be closer to 5 to be considered mature, higher than any other variety. McIntosh needs at least eight to 10 days to be mature.

Honeycrisp were sampled for the first week of the season. Honeycrisp always have a wide range of fruit maturity and this season it is more pronounced that ever; with fruit on the outside to the tree beginning to color well and to eat a little better and fruit on the inside of the tree being green as grass. I do not have any internal ethylene data to report this week.

The color of fruit sampled from the outside of the tree is 67 percent and fruit had a lower than expected firmness averaging 15.5 pounds. The starch removal averaged 2.0 with a brix of 11.6 percent. In my opinion, it is too early to jump the gun by beginning to even spot-pick Honeycrisp. There is more bitter pit showing up in Honeycrisp than any other variety.

Early Fuji were sampled for the first time of the season with 100 percent of the fruit showing internal ethylene levels greater than 0.2 ppm. The color remains fair at 70 percent and the fruit are firm at 17.9 pounds. Fruit starch removal index is 2.0 with a brix of 11.1 percent. Early Fuji are not ready for harvest; I think they are moving along fairly quickly and most likely will be ready for harvest in about a week or so.

Predicted harvest dates for southeast Michigan.

The Southeast Michigan Apple Harvest Report is produced by Bob Tritten, district fruit educator, Flint, Mich. Email tritten@msu.edu, office phone 810-244-8555, cell 810-516-3800 and fax 810-341-1729.

Looking for more? View Michigan State University Extension’s Apple Maturity Program and Reports resource page for regional reports throughout the state and additional resources.