Southeast Michigan vegetable update – May 30, 2018

Weather conditions finally allow for planting, but the effects of this spring’s wild weather will remain.

Weather

After a couple of days on unseasonable heat, rain and fairer temperatures are on deck. See below for a note about what to keep an eye out for across all crops based on recent weather conditions. While the heat has pushed us beyond where we are typically at with growing degree-days (GDD) this time of year, it happened in such a short time frame that plants are still behind.

The table below presents rainfall (in inches) for the Michigan State University Enviroweather stations in southeast Michigan, as well as growing degree-days (GDD) calculated using the Baskerville-Emin Method. Degree-day average for Commerce and Hudson is over five years, while Deerfield is over two years. Soil temperature range in Fahrenheit at 2-inch soil depth, and rainfall is in inches, with parenthesis indicating change since last Wednesday. For a refresher on degree-days and how to get this information in your area, see “Accessing growing degree days with Enviro-weather” from MSU Extension.

Rainfall and GDD totals as of May 30, 2018

Station

GDD (base 42)

GDD (base 50)

5-Year GDD average (base 50)

Rainfall since April 1

Commerce

740

450

389.9

6.8 (+0.2)

Deerfield

822

503

490.1

8.54 (+0.01)

Hudson

759

453

325

8.21 (+0.03)

General weather-related notes for all crops

There has been an explosion of transplanting in the last five days. Keep an eye on transplants that went out during the bout of extreme heat—conditions are likely to cause a lot of transplant stress. The heat dried out the topsoil (especially under black plastic) and coupled with the intense sunlight, it may be difficult for transplants to access water. The smaller the cell tray the plants were grown in, the more likely it is they’ll be struggling. The roots in the root ball aren’t those that scavenge water, new roots formed after transplanting are the ones that explore and find water. Transplants that weren’t irrigated may be stressed from lack of water, as without irrigation the only water they have had access to would be whatever moisture was in the plug at transplanting. Keep an eye on peppers especially, they like warm soil but the intense sunlight and dryness can hit them hard. Tomatoes are less likely to be affected.

Another thing we’re seeing after the cold and rainy conditions of April and May is spotty weed control. Many herbicides have a shorter active lifespan in cool, cloudy, wet conditions. As you go in to clear up problem areas, be careful with the products you use. Look at the label closely for application instructions as well as rotational restrictions, as you may be applying so late that you won’t have a full 12 months until next year’s planting season.

The rain and delayed planting also caused early-season broadcast fertilizer applications to leach or volatize. If you are sidedressing, you may need a higher rate to make up for what has been lost.

Finally, on a non-weather related note, if you are a farm that has to comply with Food Safety Modernization Act (FSMA), you may be entering the “as close as practicable to harvest” window for testing your irrigation/spray water. FSMA gives you a window to build a water-quality profile, so testing this year isn’t mandatory, but can help you work out the kinks in your testing regime and is a good agricultural practice.

For information on what to look for in a water testing lab, see MSU Extension’s “Find the right water testing lab for Food Safety Modernization Act Produce Safety Rule compliance,” and for an interactive map of Michigan labs that offer one of the FSMA-allowed testing methods, see the “FSMA Water Testing Lab Map.”

Crops

Asparagus picking is good, on some farms the end of the season is predicted to be in the next two weeks as plants were pushed hard during the heat. Asparagus beetle has been an issue statewide. A good summary of products can be found in the first table of “West central Michigan vegetable update – May 30, 2018.”

Cabbage is being transplanted. Some plantings are entering the cupping stage. Keep an eye out for the cabbage caterpillars. The below table of thresholds from the “Midwest Vegetable Production Guide” can be used when scouting to make treatment decisions, note how thresholds shift depending on plant stage. For a refresher on identifying cole crop caterpillars, see MSU Extension’s “Caterpillar Pests in Cole Crops.”

Crop

Stage

% plants with infested

Diamondback moth

Imported cabbageworm 
and cabbage looper

Cabbage

Transplant to cupping

50% with ≥ 5 larvae/plant

30% with ≥ 1 larvae/plant

Cupping to early head

50% with ≥ 5 larvae/plant

20% with ≥ 1 larvae/plant

Early head to harvest

10% with ≥ 1 larvae/plant

10% with ≥ 1 larvae/plant

Broccoli, cauliflower

Transplant to first curd

40% with ≥ 1 larvae/plant

20% with ≥ 5 larvae/plant

First curd to harvest

10% with ≥ 1 larvae/plant

10% with ≥ 5 larvae/plant

Field cucumbers are going out; some hoophouse cucumbers are being harvested. Cucumber beetles are out.

Pepper planting on bare ground is underway, peppers that went out earlier on plastic have perked up with the hot weather. See the note above about transplant stress.

In potatoes, Colorado potato beetle adults are out and mating. MSU’s new potato pathologist Jaime Wilbur is predicting there was a high likelihood of potato volunteer survival. Look out for volunteers as they serve as an inoculum source of late blight.

Rhubarb being picked has been of good quality.

The warm weather has perked up many sweet corn plantings. According to the Deerfield Enviroweather station, the first generation of European corn borer adults are flying.

Tomato planting is happening. Stakes are being placed in some fresh market fields, and light harvest of greenhouse tomatoes (both heated and unheated) has begun.

Contact me any time at 517-264-5309 or schuhmar@msu.edu with pest identification requests and questions. I tweet about what I’m seeing @SoutheastMIVeg.

Meetings

Registration for the 2018 Weed Tour on June 27 is now open. This on-campus event highlight weed identification and control strategies.

Learn more about vegetable research and management June 28 during the Agriculture Innovation Day: Focus on Fruit and Vegetable Technologies. This year’s event is being hosted at the Southwest Michigan Research and Extension Center in Benton Harbor, Michigan. More event details and registration can be found at  Agriculture Innovation Day: Focus on Fruit and Vegetable Technologies.

It is never too early to make accommodations to attend Great Lakes Fruit and Vegetable EXPO, Dec. 4-6 in Grand Rapids, Michigan. Hotel blocks are open and tend to go fast. The combination of grower-focused, research-backed presentations and an exhibit hall featuring a diverse set of vendors make it a can’t-miss event. 

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