Northwest Michigan apple maturity report – Oct. 14, 2020

Apple harvest is winding down, but later varieties, many for the processing market, are being picked at this time.

General apple harvest comments

Most growers have finished up with Honeycrisp and Gala. There are farms that are moving onto later varieties, most of which will go for processing. There are some growers that have some later-season fresh market varieties, such as LudaCrisp that are showing that they are ready for picking at this time. Evercrisp, another late variety from the Midwest Apple Improvement Association (MAIA) is still not ripe according to our testing this week. However, the flavor is still excellent, and growers anticipate them to ripen properly this season. Other older varieties, like IdaRed and Red Delicious, are ripening, but some growers will wait for the apples to mature more before harvesting. Red Delicious are still underripe at this time. The one sample of Jonagold this week were overripe, and the single Empire sample we tested is ready to be harvested. 

Quality of fruit has held for the season, despite some of the weather challenges. Watercore was a problem for some orchards early in the harvest season, but we have observed very little watercore and other kinds of internal injury for the majority of the season. Some growers were hit with hail, which was a huge disappointment for those isolated orchards. Rain events also slow harvest in the past few weeks, but we did have some really nice, sunny, fall-like days for harvest. The weather forecast is predicting more rain the coming week, and temperatures will be cool. Many growers anticipate finishing harvest in the next few weeks.  

Apple maturity in northwest Michigan for apples collected on Oct. 13, 2020

Variety

Color % (range)

Firmness lbs. (range)

Starch (range)

Brix %

Jonagold

74%

16.6

8.2

13.4

Ida Red

79%

18.5

5.2

12.9

Empire

88%

18

5.7

12.8

LudaCrisp

82%

18.9

6.8

14.6

EverCrisp

80.7% (70 - 95)

22.6 (22 - 23)

2.5 (2 - 3)

14.7 (13.7 - 15.3)

 

Jonagold maturity sampling for the harvest season

Sample date

Color % (range)

Firmness lbs. (range)

Starch (range)

Brix %

Sept. 15, 2020

90%

19.2

1.8

11.2

Sept. 22, 2020

93%

19.0

2.2

12.8

Sept. 29, 2020

88.2% (60 - 100)

18.7 (17-22)

4.4 (2-7)

13.0 (12-13.7)

Oct. 5, 2020

82.5% (50 - 100)

19.2 (15.5-22)

5.6 (4-8)

14.5 (12.5-15.5)

Oct. 13, 2020

74%

16.6

8.2

13.4

One Jonagold sample was taken this week and many of the apples we tested are approaching overmature. Firmness has decreased substantially, but the apples are holding a crunch at this time. There is some variability in the data from week to week (i.e. color appears to be reducing) due to a reduced number of samples taken this week. Many growers have already harvested this variety. 

Ida Red maturity sampling for the harvest season

Sample date

Color % (range)

Firmness lbs. (range)

Starch (range)

Brix %

Sept. 22, 2020

82%

21.8

1.1

11.4

Sept. 29, 2020

70%

19.8

1.7

11.2

Oct. 5, 2020

91% (60-100)

19.4 (17-22)

3.4 (3-5)

12.3 (11.3-12.9)

Oct. 13, 2020

79%

18.5

5.2

12.9

Ida Red are maturing, and like Jonagold, because there was only one sample taken this week, there is an unexpected decrease in color. The apples continue to hold firmness, and while starch readings suggest this variety could be harvested, growers are waiting to harvest this variety. 

Empire maturity sampling for the harvest season

Sample date

Color % (range)

Firmness lbs. (range)

Starch (range)

Brix %

Oct. 5, 2020

84%

17.3

4.7

12.2

Oct. 13, 2020

88%

18

5.7

12.8

One sample of Empire was tested this week. The apples could have been harvested last week, but color has improved. Like many other varieties, these apples have held firmness this season. 

LudaCrisp maturity sampling for the harvest season

Sample date

Color % (range)

Firmness lbs. (range)

Starch (range)

Brix %

Oct. 13, 2020

82%

18.9

6.8

14.6

With starch indices averaging 6.8 and good Brix at 14.6 degrees, the one sample of LudaCrisp tested this week is ready for harvest. They certainly are pretty with bright color this season.

EverCrisp maturity sampling for the harvest season

Sample date

Color % (range)

Firmness lbs. (range)

Starch (range)

Brix %

 

Oct. 13, 2020

80.7% (70 - 95)

22.6 (22 - 23)

2.5 (2 - 3)

14.7 (13.7 - 15.3)

 

Two samples of EverCrisp were tested this week. These apples are firm, with high Brix readings. While they are starting to taste really good, they still have some starchiness and need a little more time before they are ready to harvest for fresh eating.

Suggested firmness and starch index levels for long-term and shorter-term controlled atmosphere (CA) storage by variety.

Variety

Firmness (pounds)*

Starch Index*

Short CA

Mid-CA

Long CA

Mature

Over mature

McIntosh

14

15

16

5

7

Gala

16

17

18

3

6

Honeycrisp

15

16

17

3.5

7

Empire

14

15

16

3.5

6

Early Fuji

16

17

18

3

7

Jonagold

15

16

17

3.5

5.5

Jonathan

14

15

16

3.5

5.5

Golden Delicious

15

16

17

3

6.5

Red Delicious

16

17

18

2.5

6

Idared

14

15

16

3.5

6

Fuji

16

17

18

3

7

Rome

15

16

18

3

5.5

*Firmness is measured with a mechanical 11-millimeter wide probe inserted into the pared flesh of a fruit to a distance of 8 millimeters. Starch index is measured on equatorial cross section of an apple stained with iodine solution and rated using the Cornell University starch-iodine index chart for apples on a 1-8 scale (Predicting Harvest Date Window for Apples by Blanpied and Silsbey, Cornell Extension Bulletin 221.)

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

Did you find this article useful?


You Might Also Be Interested In