Southeast Michigan vegetable update – May 18, 2017

Warm weather has planting and field prep moving along rapidly. Be on the lookout for black cutworm, especially in weedy fields.


This hot, blustery weather will hold through today, May 18, when a new air mass with cooler than normal temperatures will move in. There is a chance of showers over the weekend.

The table below presents rainfall (in inches) for the Michigan State University Enviroweather stations in southeast Michigan, as well as degree-days (starting March 1) calculated using the Baskerville-Emin Method. Soil temperature range (top 2 inches) over the last seven days is also included when available. For a refresher on degree-days and how to get this information in your area, see “Accessing growing degree days with Enviroweather” by MSU Extension.

Rainfall and degree-day totals as of May 18


Degree-days (base 50)

6-year degree-day average (base 50)

Rainfall since April 1 (inches)














Asparagus plantings were harvested hard before last week’s frost and there was minimal damage on many operations.

Bacterial diseases have been reported in basil. This disease is seedborn and appears as very dark areas on the leaves. There aren’t a lot of products available for this disease, and afflicted plants should be destroyed.

Cole crop planting continues. Some cabbage maggot damage has been reported. I’ve heard reports of young kale plants being cut off at the base, which sounds like cutworm damage.

Pepper planting has begun.

Processing tomato planting continues. Plantings that were out during last week’s frost are recovering.

Field preparations for staked tomatoes has begun and plants are in the ground at some operations.

Sweet corn plants have generally recovered from last week’s frost and planting continues this week. Plants have up to five leaves. Some growers made treatments for flea beetles, a pest that is of concern because it can transmit Stewart’s wilt. The warm winter likely led to higher number of beetles surviving the winter; for more information on corn flea beetle and Stewart’s wilt, see Ben Phillips’ “Stewart’s wilt in sweet corn 2017” article.

Based on degree-day accumulations, black cutworm is out in some sweet corn fields, particularly fields with reduced tillage practices and where large populations of broadleaf weeds are present prior to planting. Feeding will appear as small, random holes in the leaves where the larvae are currently in development; cutting will likely commence late next week. For information on scouting and risk, see my article, “Pheromone catches of early-season pests cue sweet corn growers to do early-season scouting.”



Trap catch (5/11-5/15)

Intensive capture?

Black cutworm




True armyworm




Onions are in the ground. Some onion maggot damage has been reported. If leaves are in the one leaf stage, it is a good time to apply GoalTender for weed control.

Potatoes look healthy.

Watermelon, muskmelon and zucchini transplants are out on black plastic under low tunnels.

Contact me any time with questions at 517-264-5309 or I make updates regularly on Twitter at @SoutheastMIVeg.


It is never too early to make accommodations to attend Great Lakes Fruit and Vegetable EXPO, Dec. 5-7, 2017, in Grand Rapids, Michigan. The combination of grower-focused, research-backed presentations and an amazing exhibit hall make it a can’t-miss event.

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