Southeast Michigan fruit update – May 19, 2026
Print
EmailTree fruit are at petal fall and blueberries are in bloom.
Welcome to the eighth in-season fruit article update for southeast Michigan for the 2026 season. Throughout the season these updates will include information about the weather in the past week and the upcoming week, a fruit-by-fruit guide to current conditions with appropriate pest and disease updates, and other relevant observations.
General observations
Warm temperatures pushed fruit development forward in the last week while storms ran through with high winds, which could have brought damage to certain areas. The return of warm weather has brought out many of the insects that had become less active, with new catches of codling moth, plum curculio and San Jose scale. The weather will fluctuate this week with a mix of cool and warm temperatures and scattered showers and storms. The main disease we’re concerned about this week is apple powdery mildew, which thrives in warm, humid (but not wet) conditions. With consistent conditions we will move right into the typical cover spray schedule for the season.
Many of you will have already done spring weed control, but if not, this 2020 article on spring herbicide applications from Michigan State University Extension lists some available options.
This year, our weekly integrated pest management (IPM) updates have returned to the 2023 and 2024 format of Tuesday evening virtual meetings covering both small fruit and tree fruit in southeast and southwest Michigan. You can register online at 2026 South Michigan Fruit IPM Updates. It is a good opportunity to hear from experts, ask questions and receive restricted use pesticide (RUP) credits. See the latest weekly fruit meetings for southern Michigan on MSU’s Kaltura Media Space (these may take a few days to upload after the meetings are held).
Fruit-by-fruit conditions
Apples: Apples in the region are mostly between petal fall and fruit set, though we are seeing some protracted and lingering blooms at many farms. These lingering blooms can be a risk factor for late fire blight strikes.
Blueberries: We are bloom in cultivars like Blue Crop and Jersey, and in warmer parts of the region we are at fruit set.
Brambles: We are seeing first flowers open in summer raspberries in Romeo, new shoot growth in fall raspberries, and leafing out in blackberries.
Cherries: We are seeing fruit set in both tart and sweet cherries in most areas. The cool, extended bloom period along with frosts may result in low crop set in some farms, but it’s still too early to tell at some locations. Growers should evaluate their crop in the next week.
Grapes: We are seeing first leaves and inflorescence elongation in later hybrid wine grapes like Petite Pearl in Ray Township, while we are seeing shoot growth up to 6 inches in earlier cultivars. Growers should prepare for black rot sprays as bloom approaches.
Peaches and nectarines: Peaches are at fruit set. At some sites in the region, secondary buds are blooming in orchards where primary buds were lost.
Pears: Pears observed in Hartland were at fruit set with Bartlett at 12 mm. There seems to be a wide variation in bloom patterns depending on cultivar and the specific locations of farms.
Plums: Japanese style plums are starting to size up while European style plums are at fruit set but leaving the shuck.
Strawberries: We are seeing first fruit set and more blooms in strawberries in the region, with some new leaf development. Some areas have seen frost damage.
Insect conditions
More in-depth information can be found by watching the latest weekly fruit meetings on MSU’s Kaltura Media Space (these may take a few days to upload after the meetings).
Codling moth: A provisional biofix has been set for May 8 at Romeo. Ovicidal products can be used starting about 100 GDD base 50 after biofix (around May 20 in Romeo).
European apple sawfly: Catches have been climbing in southeast Michigan with numbers climbing. This is a pest that wasn’t an issue for many years but growers have been reporting damage in the last few seasons.
Grape berry moth: Numbers increased at Fennville. Control isn’t usually done at this time of the season.
Oriental fruit moth: Biofix was set for April 22 in Romeo and April 13 in Fennville. Numbers are up, but the control window has passed for this generation in most of the region (see the Enviroweather model with biofix).
Pear psylla: More nymphs have been caught in southeast Michigan.
Plum curculio: Counts are back up thanks to warm temperatures.
San Jose scale: Additional males have been caught in southeast Michigan and the Trevor Nichols Research Center. The next time to control is when crawlers emerge in early summer.
Tumid gallmaker: Galls can be found in many locations. If the scope is limited it won’t cause many problems, but if it becomes widespread, products like Assail can be used to control it.
Disease conditions
Apple scab: Biofix is set at green tip in McIntosh, which happened March 31. Early control of scab is important for reducing secondary scab infections that can affect fruit. We are not expecting high risk this week, though we are still in primary scab season and rain events may cause spores to eject.
Brown rot: Bloom in stone fruit is mostly over, so the control window for brown rot has passed. Read this article about brown rot control options.
Cherry leaf spot: We are not expecting high cherry leaf spot risk in the next week, though conditions could become favorable for its proliferation. See this 2024 article on cherry leaf spot management.
Fire blight: Since we are moving out of bloom, there is low fire blight risk in apples and pears this week. Cooler regions where crops are still blooming may see risk over the weekend as temperatures climb.
Grape black rot: Control for grape black rot usually begins at 1-inch shoot length, and we are there in our warmest areas. See this 2014 article on grape black rot management options and consult E-154. Risk is expected to be low this week.
Mummy berry: We are in the primary season for mummy berry infections. See E2846 for control methods.
Phomopsis: In blueberries, the Phomopsis fungus is active from bud swell until after harvest.
Powdery mildew of apple and pear: You can start to include products labeled for powdery mildew in sprays starting at tight cluster. We are expecting some risk from May 18-19.
Seasonal weather update
In the last week Southeast Michigan has seen on average about 7.1 hours of rain accumulating to roughly 0.6 inches of precipitation.
| Liquid Precipitation Accumulation Mar. 1- May 19, 2026, issued May 19, 2026 | ||||
|---|---|---|---|---|
| Station (County) | Rainfall Total (in.) Current | Hours with Rainfall Current | Rainfall Total Average (5 Yr.) | Hours with Rainfall Average (5 Yr.) |
| Commerce (Oakland) | 10.5 | 147 | 6.4 | 143 |
| Deerfield (Monroe) | 11.5 | 160 | 6.9 | 144 |
| East Lansing MSU Hort (Ingham) | 11.0 | 146 | 6.9 | 142 |
| Emmett (St. Clair) | 9.8 | 149 | 6.1 | 133 |
| Flint (Genesee) | 11.1 | 152 | 6.7 | 143 |
| Freeland (Saginaw) | 10.4 | 139 | . | . |
| Hudson (Lenawee) | 10.6 | 157 | 7.0 | 144 |
| Ithaca (Gratiot) | 12.4 | 150 | 6.1 | 133 |
| Lapeer (Lapeer) | 10.9 | 154 | 5.9 | 144 |
| Linwood (Bay) | 11.3 | 160 | 5.8 | 126 |
| Pigeon (Huron) | 9.4 | 161 | 5.2 | 134 |
| Richville/Frankenmuth (Tuscola) | 11.1 | 147 | 6.4 | 130 |
| Romeo (Macomb) | 9.5 | 132 | 6.4 | 134 |
| Sandusky (Sanilac) | 9.5 | 135 | 5.8 | 128 |
| Average of stations in this region: | 10.6 | 149.2 | 6.3 | 136.8 |
| Difference in Liquid Precipitation Accumulation from Mar. 1 observed May 12 and May 19, 2026; issued May 19, 2026 | ||||||
|---|---|---|---|---|---|---|
| Rainfall Total (in.) | Rainfall Total (in.) | Hours with Rainfall | Hours with Rainfall | |||
| Station (County) | 12-May | 19-May | Difference | 12-May | 19-May | Difference |
| Commerce (Oakland) | 9.3 | 10.5 | 1.2 | 138 | 147 | 9.0 |
| Deerfield (Monroe) | 10.2 | 11.5 | 1.3 | 153 | 160 | 7.0 |
| East Lansing MSU Hort (Ingham) | 10.6 | 11.0 | 0.4 | 142 | 146 | 4.0 |
| Emmett (St. Clair) | 9.1 | 9.8 | 0.7 | 143 | 149 | 6.0 |
| Flint (Genesee) | 10.2 | 11.1 | 0.9 | 143 | 152 | 9.0 |
| Freeland (Saginaw) | 10.0 | 10.4 | 0.4 | 132 | 139 | 7.0 |
| Hudson (Lenawee) | 10.3 | 10.6 | 0.4 | 150 | 157 | 7.0 |
| Ithaca (Gratiot) | 12.1 | 12.4 | 0.3 | 145 | 150 | 5.0 |
| Lapeer (Lapeer) | 10.5 | 10.9 | 0.4 | 149 | 154 | 5.0 |
| Linwood (Bay) | 10.8 | 11.3 | 0.5 | 152 | 160 | 8.0 |
| Pigeon (Huron) | 9.0 | 9.4 | 0.4 | 150 | 161 | 11.0 |
| Richville/Frankenmuth (Tuscola) | 10.7 | 11.1 | 0.5 | 142 | 147 | 5.0 |
| Romeo (Macomb) | 8.4 | 9.5 | 1.1 | 121 | 132 | 11.0 |
| Sandusky (Sanilac) | 8.9 | 9.5 | 0.7 | 130 | 135 | 5.0 |
| Average of stations in this region: | 10.0 | 10.6 | 0.6 | 142.1 | 149.2 | 7.1 |
In the short term we are expecting cool and cloudy conditions mid-week, showers on Friday into Saturday, and then a warm-up with fair conditions over the weekend. Highs will be in the 60s and then warm to the 80s. Lows will go between the 40s and 50s for most of the next week but we don’t expect risk for frost.
In the medium term, we are expecting temperatures to be near to above normal and precipitation totals to be normal to above normal. The long lead outlooks are calling for both temperature and precipitation to be near normal.
Our regional average growing degree day accumulation for the season are about 10 days ahead of the long-term normals and about a week ahead of the five-year average. In the last week, we accumulated on average 124 GDD at 48 F, 106 GDD at 45 F and 78 GDD at 50 F (see table below). Read this Michigan State University Extension article to learn more about degree days: Understanding growing degree-days.
| Degree Day Accumulation Mar. 1-May 19, 2026 Forecast from May 20- May 26, 2026; issued May 19, 2026 | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Station (County) | Degree Days Base 42°F Current | Degree Days Base 42°F Average (5 Yr.) | Degree Days Base 42°F Forecast | Degree Days Base 45°F Current | Degree Days Base 45°F Average (5 Yr.) | Degree Days Base 45°F Forecast | Degree Days Base 50°F Current | Degree Days Base 50°F Average (5 Yr.) | Degree Days Base 50°F Forecast |
| Commerce (Oakland) | 657 | 589 | 792 | 526 | 465 | 640 | 348 | 301 | 430 |
| Deerfield (Monroe) | 824 | 705 | 968 | 670 | 564 | 794 | 452 | 374 | 543 |
| East Lansing MSU Hort (Ingham) | 731 | 632 | 866 | 592 | 502 | 707 | 399 | 329 | 483 |
| Emmett (St. Clair) | 575 | 557 | 694 | 455 | 437 | 555 | 293 | 278 | 363 |
| Flint (Genesee) | 706 | 649 | 840 | 572 | 519 | 686 | 387 | 343 | 469 |
| Freeland (Saginaw) | 576 | 577 | 696 | 457 | 457 | 556 | 293 | 297 | 362 |
| Hudson (Lenawee) | 756 | 638 | 896 | 614 | 509 | 734 | 417 | 338 | 504 |
| Ithaca (Gratiot) | 658 | 621 | 785 | 529 | 494 | 636 | 353 | 324 | 429 |
| Lapeer (Lapeer) | 672 | 609 | 798 | 546 | 485 | 653 | 372 | 319 | 447 |
| Linwood (Bay) | 484 | 499 | 593 | 373 | 388 | 462 | 229 | 246 | 289 |
| Pigeon (Huron) | 502 | 502 | 615 | 393 | 391 | 485 | 246 | 249 | 308 |
| Richville/Frankenmuth (Tuscola) | 632 | 608 | 757 | 508 | 483 | 613 | 339 | 314 | 414 |
| Romeo (Macomb) | 649 | 587 | 777 | 518 | 461 | 626 | 340 | 294 | 417 |
| Sandusky (Sanilac) | 551 | 439 | 659 | 435 | 423 | 524 | 278 | 272 | 338 |
| Average of stations in this region: | 641 | 587 | 767 | 513 | 470 | 619 | 339 | 306 | 414 |
| Difference in Degree Day Accumulation from Mar. 1, 2026 observed May 12 and May 19, 2026; issued May 19, 2026 | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Station (County) | Degree Days Base 42°F | Degree Days Base 42°F | Degree Days Base 42°F | Degree Days Base 45°F | Degree Days Base 45°F | Degree Days Base 45°F | Degree Days Base 50°F | Degree Days Base 50°F | Degree Days Base 50°F |
| 12-May | 19-May | Difference | 12-May | 19-May | Difference | 12-May | 19-May | Difference | |
| Commerce (Oakland) | 535 | 657 | 122.0 | 421 | 526 | 105.0 | 269 | 348 | 79.0 |
| Deerfield (Monroe) | 690 | 824 | 134.0 | 554 | 670 | 116.0 | 365 | 452 | 87.0 |
| East Lansing MSU Hort (Ingham) | 594 | 731 | 137.0 | 474 | 592 | 118.0 | 310 | 399 | 89.0 |
| Emmett (St. Clair) | 458 | 575 | 117.0 | 355 | 455 | 100.0 | 219 | 293 | 74.0 |
| Flint (Genesee) | 570 | 706 | 136.0 | 455 | 572 | 117.0 | 298 | 387 | 89.0 |
| Freeland (Saginaw) | 455 | 576 | 121.0 | 355 | 457 | 102.0 | 219 | 293 | 74.0 |
| Hudson (Lenawee) | 631 | 756 | 125.0 | 508 | 614 | 106.0 | 337 | 417 | 80.0 |
| Ithaca (Gratiot) | 528 | 658 | 130.0 | 419 | 529 | 110.0 | 271 | 353 | 82.0 |
| Lapeer (Lapeer) | 545 | 672 | 127.0 | 436 | 546 | 110.0 | 288 | 372 | 84.0 |
| Linwood (Bay) | 375 | 484 | 109.0 | 282 | 373 | 91.0 | 164 | 229 | 65.0 |
| Pigeon (Huron) | 392 | 502 | 110.0 | 300 | 393 | 93.0 | 179 | 246 | 67.0 |
| Richville/Frankenmuth (Tuscola) | 505 | 632 | 127.0 | 399 | 508 | 109.0 | 259 | 339 | 80.0 |
| Romeo (Macomb) | 526 | 649 | 123.0 | 413 | 518 | 105.0 | 262 | 340 | 78.0 |
| Sandusky (Sanilac) | 438 | 551 | 113.0 | 339 | 435 | 96.0 | 208 | 278 | 70.0 |
| Average of stations in this region: | 517 | 641 | 124 | 408 | 513 | 106 | 261 | 339 | 78 |
Watch Jeff Andresen's weekly agricultural weather forecast reports
More information and reports on normal weather conditions and departures from normal can be found on the NOAA Climate Prediction Center website, NOAA U.S. Climate Normals website, NOAA Climate Normals Quick Access Page (which may be searched by region), and Midwest Regional Climate Center website.
This work is supported by the Crop Protection and Pest Management Program [grant no 2024-70006-43569] from the USDA National Institute of Food and Agriculture. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture.
