Northwest Michigan apple maturity report – Sept. 18, 2019
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EmailApple harvest is beginning in earnest and Honeycrisp are showing up in markets.
General apple harvest comments
Apple harvest has really started to begin in earnest this week. Most Ginger Golds are off the tree and SweeTango harvest is ongoing; growers are starting to move onto the more mainstream varieties, such as Honeycrisp and Gala. It has been interesting in that some strains/blocks of Gala are being harvested before Honeycrisp. Many growers are waiting for better color on Honeycrisp, but overall this variety has pretty good color across the board.
Some growers have used reflective material in the orchard to improve color. We have also heard that growers summer pruned to improve color and have been pleased with the results (see photos). Even with the warm temperatures during the day, nighttime temperatures have been in the 50s, which has helped with color. Some growers are starting to spot-pick Honeycrisp, and this variety is on all farm stands throughout the region.
Fruit firmness seems to be holding, but growers are concerned with the predicted heat for the remainder of the week. The forecast for today, Wednesday, Sept. 18, is for the daytime temperature to hit in the high 70s or low 80s. In anticipation of the heat, growers are using plant growth regulators to prevent premature dropping. Fruit is eating really good, even with starch conversion readings in lower ranges. There is variability in starch conversion readings across strains and samples in different blocks in the region.
Brix levels are relatively good across all varieties. Brix readings on some of the SweeTango we tested were high, even hitting 16 brix for some apples. Again, apples are tasting very good at this stage of the season, and growers are eager to move into full-fledged harvest.
|
Apple maturity in northwest Michigan for apples collected on Sept. 17, 2019 | ||||
|---|---|---|---|---|
|
Variety |
Color % (range) |
Firmness lbs. (range) |
Starch (range) |
Brix % |
|
SweeTango |
85.0 (82.0 - 88.0) |
17.42 (16.2 - 18.6) |
4.5 (4.2 - 4.9) |
13.9 (11.6 - 16.1) |
|
Honeycrisp |
70.1 (57.5 - 78.5) |
18.2 (16.5 - 18.7) |
3.4 (1.8 - 4.9) |
13.1 (12.2 - 15.2) |
|
Gala |
78.0 (54.0 - 95.0) |
21.2 (16.8 - 23.0) |
1.1 (1.0 - 1.7) |
11.6 (10.0 - 14.5) |
|
McIntosh |
63.0 (29.5 - 92.5) |
16.5 (15.0 - 18.2) |
2.3 (2.2 - 2.4) |
11.0 (10.9 - 11.1) |
|
Early Jonathan |
80.0 |
16.9 |
1 |
13.2 |
Individual variety results
SweeTango
SweeTango harvest is ongoing, and these apples continue to eat really well. Color is good to excellent across the region and the apples are holding firmness.
|
SweeTango maturity sampling for the harvest season | ||||
|---|---|---|---|---|
|
Sample date |
Color % (range) |
Firmness lbs. (range) |
Starch (range) |
Brix % |
|
Sept. 10 |
89.3 (80.0 - 100) |
16.95 (15.0 - 20.0) |
3.2 (1.5 - 5.0) |
13.1 (10.8 - 15.8) |
|
Sept. 17 |
85.0 (82.0 - 88.0) |
17.42 (16.2 - 18.6) |
4.5 (4.2 - 4.9) |
13.9 (11.6 - 16.1) |
Honeycrisp
We sampled five Honeycrisp blocks this week. Color is good on most blocks of Honeycrisp, and growers have gone to extra lengths to get better color this season. Honeycrisp is still firm, and most fruit is juicy and flavorful. We do not see much bitter pit in this variety this season.
|
Honeycrisp maturity sampling for the harvest season | ||||
|---|---|---|---|---|
|
Sample date |
Color % (range) |
Firmness lbs. (range) |
Starch (range) |
Brix % |
|
Sept. 4 |
50.5 (44.5 - 56.5) |
19.6 (19.2-20.0) |
1.0 (1.0 - 1.0) |
10.8 (10.4 - 11.2) |
|
Sept. 10 |
53.9 (40.0 - 95.0) |
18.6 (17.0 - 21.0) |
1.4 (1.0 - 3.0) |
11.5 (10.0 - 13.0) |
|
Sept. 17 |
70.1 (57.5 - 78.5) |
18.2 (16.5 - 18.7) |
3.4 (1.8 - 4.9) |
13.1 (12.2 - 15.2) |
Gala
There is variability in Gala in terms of size and color this season. We tested five blocks this week and apples in some of these blocks are still on the small size; however, size is excellent in the block at the Northwest Michigan Horticulture Research Center. Color is also really good on the apples at the station and they are eating very well, despite the starch removal index being only a 1 or 2 and an occasional 3. Gala at the station are also a bit on the waxy side, which again is interesting because starch readings suggest that the apples are not mature yet.
|
Gala maturity sampling for the harvest season | ||||
|---|---|---|---|---|
|
Sample date |
Color % (range) |
Firmness lbs. (range) |
Starch (range) |
Brix % |
|
Sept. 10 |
64.0 (30.0 - 95.0) |
22.3 (19.0 - 23.0) |
1.0 (1.0 - 1.0) |
9.8 (8.5 - 11.5) |
|
Sept. 17 |
78.0 (54.0 - 95.0) |
21.2 (16.8 - 23.0) |
1.1 (1.0 - 1.7) |
11.6 (10.0 - 14.5) |
McIntosh
We tested three McIntosh blocks including a block of Linda Mac and Macspur this week. Macs still have a green background, even on Macspur. The flavor of Macs does not seem as distinct as usual for this time of year. Color on Macs is pretty good and still relatively firm. Growers are concerned about the heat and drop of Macs. This variety is still eating quite green.
|
McIntosh maturity sampling for the harvest season | ||||
|---|---|---|---|---|
|
Sample date |
Color % (range) |
Firmness lbs. (range) |
Starch (range) |
Brix % |
|
Sept. 10 |
74.3 (15.0 - 100) |
16.1 (13.5 - 19.5) |
1.7 (1.0 - 3.0) |
10.6 (9.7 - 11.4) |
|
Sept. 17 |
63.0 (29.5 - 92.5) |
16.5 (15.0 - 18.2) |
2.3 (2.2 - 2.4) |
11.0 (10.9 - 11.1) |
|
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.)
