Grand Rapids area apple maturity report – August 29, 2024
Print
EmailSecond apple maturity report and integrated pest management updates.
Weather update and integrated pest management impacts
We are expecting cooler temperatures this week with nighttime lows in the 50s and 60s. This will help fruit reddening. Daytime temperatures will increase this weekend with high temperatures predicted at 88 degrees Fahrenheit.
Crop update
Apple harvest is well underway! Honeycrisp, Galas and McIntosh varieties are now being considered for harvest across the area. Early Fujis are also moving into their harvest window.
Please keep in mind that stop-drop materials can be very useful to manage harvest windows during this early season, especially if color is a concern, and the windows to effectively use them are sooner rather than later.
This is a difficult harvest season to balance between harvest metrics and visual quality with reddening. Stop-drop materials, reflective ground covers and summer pruning are being used effectively throughout the region to encourage color. Please keep in mind that waiting to harvest can impact the long-term storage and quality of the crop. Maintaining fruit quality and long-term integrity is crucial this year.
Some of these varieties coming into maturity are even exceeding the early predicted harvest dates by Michigan State University Extension this year. Frequent proactive sampling will be needed to stay on top of harvest. Please let me know if there are other varieties you would like me to sample.
Fuji
This variety was sampled at two locations in Kent County this week. The later season Fujis are still a few weeks away from maturity.
|
Collection Date |
Weight (g) |
Red Color (%) |
Background Color |
Diameter (mm) |
Firmness (lbs) |
Starch |
Soluble Solids (°Brix) |
|---|---|---|---|---|---|---|---|
|
8/20/2024 |
|
43 (20 - 70) |
2.5 (2-3) |
68.2 (59.4 - 74.5) |
22.4 (19.7 - 29.4) |
1.8 (1 - 2) |
9.1 (9 - 9.3) |
|
8/28/2024 |
147.2 (86-220) |
55.3 (30-90) |
2.3 (1-3) |
68.1 (60-79)
|
23.3 (20.4-27.7) |
2.1 (1-3) |
10 (9.4-11) |
Gala
This variety was sampled across three locations in Kent County this week. Galas are moving into their harvest window soon. They taste excellent! Keep an eye on Galas in the next week. The firmness is still too high for optimal maturity and sugars need to develop further, but the starch index is in line with maturity.
|
Collection Date |
Weight (g) |
Red Color (%) |
Background Color |
Diameter (mm) |
Firmness (lbs) |
Starch |
Soluble Solids (°Brix) |
|---|---|---|---|---|---|---|---|
|
8/20/2024 |
|
76.8 (15 - 95) |
1.6 (1-3) |
68.9 (57.6 - 82) |
21.3 (16.4 - 27.6) |
2.4 (1 - 4) |
10.2 (9 - 13.8) |
|
8/28/2024 |
155 (109-222) |
82.5 (30-95) |
1 (1-1) |
68.8 (33-72) |
20.3 (16.7-27.8) |
3.2 (1-5) |
10.3 (8.8-12) |
Honeycrisp
This variety was sampled across three locations in Kent County this week. Note that the average firmness is in line with controlled atmosphere (CA) storage recommendations and the starch index is mature and becoming overmature quickly. These apples taste excellent, and the sugars are fair. The reddening was further along compared to last week.
|
Collection Date |
Weight (g) |
Red Color (%) |
Background Color |
Diameter (mm) |
Firmness (lbs) |
Starch |
Soluble Solids (°Brix) |
|---|---|---|---|---|---|---|---|
|
8/20/2024 |
|
58.9 (20 - 95) |
2 (1 - 3) |
80.1 (68.1 - 101.9) |
16.3 (11.5 - 21.7) |
3.5 (1 - 7) |
12.1 (10.2 - 14) |
|
8/28/2024 |
222.9 (131-222) |
64.3 (20-95) |
2.1 (1-3) |
79.2 (65-94) |
16.4 (14.1-27.8) |
5.03 (3-5) |
12.2 (10.5-12.2) |
Premier Honeycrisp
This variety was sampled at two locations in Kent County this week. This variety is overmature now. Most Premier Honeycrisps that weren’t picked yet were knocked off the trees by the thunderstorm this week.
|
Collection Date |
Weight (g) |
Red Color (%) |
Background Color |
Diameter (mm) |
Firmness (lbs) |
Starch |
Soluble Solids (°Brix) |
|---|---|---|---|---|---|---|---|
|
8/20/2024 |
|
73 (45 - 90) |
1.7 (1 - 3) |
75.6 (68.8 - 82.7) |
13.5 (10.1 - 15.6) |
6.1 (5 - 7) |
13.2 (12.1 - 14.8) |
|
8/28/2024 |
170.6 (114-229) |
54.8 (30-80) |
1.7 (1-3) |
74.1 (66-82) |
13.3 (11.4-16.6) |
6.9 (5-8) |
10.8 (9.2-12.5) |
LindaMac
This variety was sampled at three locations in Kent County. Keep an eye on RubyMacs and LindaMacs this upcoming week when making harvest decisions. While sugars are not ideal, the firmness and starch are in line with maturity metrics. Color is good on McIntosh sports in the area this week.
|
Collection Date |
Weight (g) |
Red Color (%) |
Background Color |
Diameter (mm) |
Firmness (lbs) |
Starch |
Soluble Solids (°Brix) |
|---|---|---|---|---|---|---|---|
|
8/28/2024 |
140.7 (82-227) |
75.7 (40-95) |
2.4 (1-4) |
71.0 (60.6-85.3) |
16.6 (12.4-19.4) |
5.0 (4-6) |
10.7 (10-12.8) |
Pest and disease update
Obliquebanded leafroller spike
Of note, there has been a spike in obliquebanded leafroller populations recently. A similar late season spike occurred in 2019, according to Julianna Wilson. This is likely due to conducive weather conditions for the insect, not associated with another generation. These high populations are not likely to result in fruit damage. Additionally, keep in mind that obliquebanded leafroller are strong fliers and high numbers in a trap do not necessarily indicate high populations in the immediate area. While it can be alarming to see high numbers in traps at this point in the year, they do not necessarily need to be sprayed for. I’ll be sure to remind you all about this spike early next season.
Woolly apple aphids
I saw a couple well developed woolly apple aphid colonies in the area this week. Please keep last minute controls in mind as they can make harvesting uncomfortable.
Fruit rots
Keep up control measures for bitter rot and black rot! Be sure to save a shot of Merivon for directly before harvest.
For more information about regional reports, please visit the Michigan State University Extension website.
