East Michigan vegetable regional report – June 28, 2017

Harvest of warm season crops is ramping up. So is disease pressure.

Weather

Growers north of M-46, south of Gladwin, Michigan, and east of US-127 to the Bay received excessive rainfall over the last week. Michigan State University Enviroweather stations accumulated between 1.39 (Ithaca) and 6 inches (Linwood) between June 19 and June 26, 2017, but growers have reported much higher accumulations, reaching 11 inches in Merrill, Michigan, and 8 inches in Essexville, Michigan, and Gladwin, Michigan. 

Two important and destructive diseases showed up to our east in Ontario on Tuesday, June 27: late blight in tomatoes, and downy mildew in cucumbers and cantaloupes.

The table below shows growing degree-days (GDD) base 50 degrees Fahrenheit since March 1, rainfall (inches since April 1) accumulations and soil temperature ranges (Fahrenheit over the last week) to date from MSU Enviro-weather stations in the region.

Rainfall and GDD totals as of June 28, 2017

Location

GDD (+ added from last week)

GDD 5-year average

Rainfall (+ added from last week)

Rainfall 5-year average

Emmett

735 (+ 139)

868.4

8.15 (+ 1.26)

7.25

Fairgrove

772 (+ 128)

885.8

7.67 (+ 2.29)

7.54

Flint

864 (+ 140)

963.1

10.72 (+ 1.65)

10.11

Frankenmuth

812 (+ 133)

926.5

10.21 (+ 2.15)

8.07

Freeland

790 (+ 135)

915.9

6.98 (+ 0.06)

8.58

Lapeer

796 (+ 123)

925.5

6.85 (+ 1.65)

9.31

Linwood

709 (+ 129)

835.9

13.76 (+ 3.77)

8.61

Munger

793 (+ 135)

916.1

8.96 (+ 1.51)

7.65

Romeo

799 (+ 144)

925.7

7.57 (+ 0.91)

8.24

Sandusky

695 (+ 128)

832.6

8.34 (+ 1.73)

8.37

Crops

Sweet corn plantings are finishing up in many places. Silks are out. European corn borer and corn earworm are potential pests at this point.

The recent rains impacted pickling cucumbers in the flood zones in Isabella, Mecosta, Clare, Gladwin, Arenac, Saginaw and Bay counties, and processors are communicating to their growers with adjustments to planting and harvest schedules where it is needed. Initial estimates were between 5-50 percent loss of recently planted pickles in the flooded region, but the extent of damage has not been fully realized.

I wrote an MSU Extension article with instructions for making stand count assessments for pickles once ground dries. Phytophthora infections may be an issue in those fields with an infection history.

To make matters more hectic, downy mildew was found in Essex County, Ontario, Tuesday, June 27, in cucumber and cantaloupe. MSU plant pathologist Mary Hausbeck’s downy mildew recommendations for 2017 suggests at least a three-product rotation of Ranman SC, alternated with Previcur Flex SL and Zampro SC. Each material needs to be tank-mixed with Bravo Weatherstik. Once downy mildew is in neighboring counties, add Orondis Opti SC to the rotation no more than once every three sprays. For Monroe County growers, that is now.

Watermelons and cantaloupes are setting fruit. Downy mildew was found in Ontario. See pickle section for fungicide recommendations.

Zucchini and yellow summer squash harvest has begun. Squash vine borer is flying and laying eggs.

I ate my first fresh market field tomatoes last week. They were delicious. Hoophouse tomatoes with poor ventilation and tight plant spacing are coming down with early blight and bacterial infections. Tomato late blight was found in Chatham-Kent, Ontario, yesterday, June 27. Growers should begin regular applications of Bravo Weatherstik when cloudy and humid conditions favor the disease.

Red beets and radishes are being planted and harvested, nearly weekly.

The Midwest Mechanical Weed Control Field Day is scheduled for Sept. 26 at the MSU Horticulture Farm. For more information and registration, see “Midwest Mechanical Weed Control Field Day.

Hotels are filling up for the Great Lakes Fruit and Vegetable EXPO, Dec. 5-7 in Grand Rapids, Michigan. The combination of grower-focused, research-backed presentations and an amazing exhibit hall make it a can’t-miss event.

Please contact me at phill406@msu.edu or 616-901-7513 to pick up any suspected disease samples from your farm, or send the diseased plant parts to MSU Diagnostic Services.

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