West central Michigan apple maturity report – September 4, 2025
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EmailCooler temperatures continue this week, and a storm brought much needed rain to the region.
Apple maturity testing will occur weekly for the west central Michigan region beginning now through the end of harvest. Reports will be sent out every week following the Michigan State University Extension fruit team apple maturity calls on Wednesday mornings.
In the west central region, early apple varieties of Wildfire Gala and Premier Honeycrisp are being harvested this week. Minneiska is also being harvested. Honeycrisp, McIntosh and Brookfield and Pacific strains of Gala are still immature. Jonagold is also immature.
Weather over the past few days has been cooler with low temperatures dipping down into the 50s or upper 40s across the region. Day and nighttime temperatures will remain cool over the next few days and through the weekend with highs in the upper 50s and low 60s. Low temperatures will be in the 40s and 50s. Chances of rain are in the forecast for the rest of the week.
How to read maturity tables
Each week, an apple maturity report will be provided and will include average values for several apple samples for varieties nearing maturity. Maximum and minimum values are included in tables below for the highest and lowest individual fruits evaluated for each to give a full spectrum of maturity. All samples included in the reports have been untreated with ReTain or Harvista, unless otherwise noted. Samples were collected from two to five locations across Oceana County.
For more information about apple maturity testing, review these resources compiled by the MSU Extension tree fruit team.
- Predicted apple harvest dates for 2025 from MSU.
- More information on harvest management tools and timings can be found in this article.
- Guidelines from MSU to check for apple maturity in your own orchard, including specific pressure and starch recommendations by variety.
- New starch charts for evaluating apple maturity in Michigan from Michigan State University
- Predicting apple maturity and starch chart from Cornell University.
- Starch chart for Honeycrisp Apples developed by Washington State University.
Maturity information for the west central region
Minneiska
Minneiska fruit were sampled at two locations on Sept. 2 in Oceana County. Red color development improved by about 20% from last week. Background color is light yellow. Starch is clearing into the cortex, and sugar levels are excellent at 14.3 Brix. Growers are harvesting this variety this week.
|
Collection Date |
Fruit Weight (g) |
Red Color (%) |
Background color (5-1) |
Firmness (lbs) |
Starch (1-8) |
Soluble Solids (°Brix) |
|---|---|---|---|---|---|---|
|
Aug 25 |
167 (185-159) |
61 (98-25) |
2.9 (4-1) |
16.2 (18.0-14.2) |
2.2 (4-1) |
12.9 (14.2-11.6) |
|
Sept 2 |
188 (210-166) |
83 (100-50) |
1 (1-1) |
15.9 (18.6-13.6) |
3.1 (5-2) |
14.3 (14.3-14.2) |
RubyMac
Fruit were harvested from two locations in Oceana County. RubyMac is a red coloring strain of McIntosh and is at a similar stage of maturity to standard strains of McIntosh in the area. Fruit are dark red and cover 93% of the surface. Background color is still green. Average firmness is at 16.1 pounds. Recommended pressure for long-term controlled atmosphere (CA) is 16 pounds. Fruit is still immature at a starch rating of 2.6. McIntosh are mature at a starch test of 5. Sugar levels are good at this stage with Brix at 11.7.
|
Collection Date |
Fruit Weight (g) |
Red Color (%) |
Background color (5-1) |
Firmness (lbs) |
Starch (1-8) |
Soluble Solids (°Brix) |
|---|---|---|---|---|---|---|
|
Aug 25 |
146 (164-127) |
78 (98-50) |
5 (5-5) |
17.8 (21.4-15.0) |
1.9 (3-1) |
11.7 (12.0-11.4) |
|
Sept 2 |
169 (196-142) |
93.4 (100-90) |
4.55 (5-4) |
16.1 (18.4-14. 5) |
2.6 (3-2) |
12.7 (13.5-11.8) |
Gala
Gala fruit were sampled from five locations in Oceana County this week. The samples in the table below are for Brookfield and Pacific Gala. Fruit size is small in the region, but recent rains should help improve fruit size. Red color improved from last week and is at 76%. Background color is yellow at 2.2. Fruit firmness is at 18.9 pounds of pressure. Starch is an average of 1.4. Sugars are an average of 9.7 Brix.
|
Collection Date |
Fruit Weight (g) |
Red Color (%) |
Background color (5-1) |
Firmness (lbs) |
Starch (1-8) |
Soluble Solids (°Brix) |
|---|---|---|---|---|---|---|
|
Aug 25 |
131(150-112) |
58 (99-20) |
2.9 (4-1) |
21.1 (24.5-13.9) |
1.3 (8-1) |
9.6 (11.6-8.6) |
|
Sept 2 |
143 (167-127) |
76 (100-45) |
2.2 (4-1) |
18.9 (22.7-16.4) |
1.4 (3-1) |
9.7 (11.0-7.4) |
Honeycrisp
Fruit were sampled from five locations in Oceana County. Red color is improving at 63%. Red color and size will continue to improve over the next few days following cooler daytime temperatures and cool nights in the 50s. Background color is light green, and fruit are still immature. Pressure is 15.7 pounds, and starch rating averaged at 1.2, similar to last week. Sugars are at 10.1 Brix.
Bitter pit development on fruit has been observed in some locations. Fruit that are high risk or are more susceptible to bitter pit development may be in blocks with younger trees, high-risk rootstocks, high-vigor trees, or low crop loads. Large fruit are also more susceptible to bitter pit development than small fruit. High bitter pit-risk fruit should be cooled quickly to the recommended 38 degrees Fahrenheit storage temperature, as conditioning will exacerbate bitter pit. High risk fruit should be marketed as soon as possible. Fruit intended for longer storage should be pre-conditioned, with recommended conditions of 50 F (room temperature) for five to seven days.
|
Collection Date |
Fruit Weight (g) |
Red Color (%) |
Background color (5-1) |
Firmness (lbs) |
Starch (1-8) |
Soluble Solids (°Brix) |
|---|---|---|---|---|---|---|
|
Aug 25 |
181 (230-133) |
54 (90-15) |
4.9 (5-4) |
17.9 (22.7-15.1) |
1.7 (8-1) |
10.9 (11.8-9.2) |
|
Sept 2 |
212 (241-201) |
63 (95-40) |
3.2 (4-2) |
15.7 (19.6-12.9) |
1.2 (3-1) |
10.1 (11.6-8.4) |
Jonagold
Jonagold fruit were sampled from five locations in Oceana County. Red color is at 88%, and background color is green at 3.9. Fruit firmness is at 19.8 pounds of pressure. Starch is an average of 1.5. Sugars are low at an average of 10.1 Brix.
|
Collection Date |
Fruit Weight (g) |
Red Color (%) |
Background color (5-1) |
Firmness (lbs) |
Starch (1-8) |
Soluble Solids (°Brix) |
|---|---|---|---|---|---|---|
|
Sept 2 |
176 (194-165) |
88 (100-60) |
3.9 (4-3) |
19.8 (28.2-15.8) |
1.5 (3-1) |
10.1 (12.3-7.4) |
Apple maturity sampling parameters
- Color % = the visual percentage of red color from 0 to 100; range is of all fruits tested. Indicates surface area covered in red and intensity of red color.
- Background color: 5 = Green, 1 = Yellow; range is of all fruits tested.
- Firmness in pounds pressure = measured with a Güss Fruit Texture Analyzer; range is of all fruits tested.
- Starch For Honeycrisp: will typically be rated using the standard Michigan State University starch scale (1-8). However, a separate starch chart for Honeycrisp Apples developed by Washington State University (scale 1-6) also exists.
- Brix = % sugar measured with Atago PAL-1 Pocket Refractometer
Looking for more? View Michigan State University Extension’s Apple page for regional reports throughout the state and additional resources.
|
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 |
6 |
|
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 |
|
Brix Guide |
Low |
Fair |
Good |
Excellent |
|
All varieties |
Less than 11 |
11 |
12 |
13 |
|
Honeycrisp |
Less than 12 |
12 |
12 |
Greater than 14 |
