East Michigan vegetable update – May 9, 2018

Vegetable plantings and weed control applications continue. Overwintered seed and root maggot flies have begun emerging.

Weather

Some growers lost power and plastic from hoophouses on Friday last week, May 4.

Between 0.25 – 2 inches of rain can be expected across our region by the weekend. Friday morning, May 11, will get down into the 30s, and there is a potential for frost in the northern Lower Peninsula.

I am changing the way I report from the Michigan State University Enviroweather stations in our region. I decided it would be more relevant to report growing degree-days (GDD) with base temperatures that are relevant to some of our vegetable pests.

  • Base 39: seed corn maggot
  • Base 40: onion maggot
  • Base 43: cabbage maggot
  • Base 45: variegated cutworm
  • Base 50: Colorado potato beetle, common asparagus beetle, corn rootworm, European corn borer, flea beetles, imported cabbageworm, squash vine borer.

As important life stages are triggered by GDDs, I will make note of them in the report.

Here are GDDs and rainfall accumulations to date starting Jan. 1 in the region.

Location

GDD39

GDD40

GDD43

GDD45

GDD50

Rainfall (inches)

Emmett

401.7

368.8

283.5

235.8

148.5

7.25

Fairgrove

408.2

376.6

294.9

248.6

157.7

7.87

Flint

492.8

454.4

356.4

300.9

192.9

7.66

Frankenmuth

427.2

394.9

310.4

263.1

169.8

6.69

Freeland

406.8

374.1

290.7

245.9

157.9

6.91

Lapeer

448.3

413.6

323.7

273.3

174.4

12.29

Linwood

371.8

340.8

260.0

215.5

132.8

8.78

Munger

393.3

361.2

276.0

229.5

142.9

5.37

Romeo

469.8

432.8

335.9

281.7

177.2

8.08

Sandusky

369.4

338.7

259.6

217.9

140.5

7.66

In my report, I make an effort to report on what I’m seeing on farms of all sizes. If you are a small farm looking for information on what’s happening on other small farms across the state, you can subscribe (and even submit) to the Michigan Small Farm Network. To subscribe to this newsletter, which crowdsources reports from small farms across the state, fill out the linked form at the MSU Small Farm Network webpage.

Crops

Asparagus is up and first pickings will commence soon.

Strawberries are slowly putting on new leaves from the crown and flower trusses are beginning to emerge in the earliest varieties. MSU Extension fruit educator Bob Tritten recommends a light application of 15 pounds actual nitrogen to encourage some growth in this cool spring.

Red beets are up and plantings continue. For organic production, MSU horticulturist Dan Brainard recommends using a stale seedbed technique with a flex-tine harrow before or immediately following seeding to eliminate germinating weeds in the top inch of soil. Seed the beets as straight as you can with an increased population. After emergence, finger weeders can be used to thin the beet stand and remove in-row weeds.

I think the Bay and Thumb vegetable growers are uniquely positioned to produce massive quantities of red beets for processing. Since the sugar beet industry went to RoundUp ready beets and mono-germ beets, the Pickett combination row thinners and in-row cultivation tools have been sitting at the back of barns and equipment yards. Centrifugal pull-type harvesters are being phased out for self-propelled machines. With some modification, I think both the thinners and the pull-type harvesters could be employed for red beets.

Green beans are just coming up and plantings continue.

Brassicas are still going in and degree-days base 43 indicate overwintered cabbage maggot flies are just starting to emerge.

Sweet corn is up from the earliest plantings under plastic and bare ground seeding continues. According to degree-day models base 39, overwintered seedcorn maggot flies are in their peak egglaying period.

Seeded squash and pumpkin is coming up and some growers may consider applying a fungicide for phytopthora. MSU plant pathologist Mary Hausbeck has noticed germination reduction when Ridomil is used as an in-furrow application at seeding, premixed with a starter fertilizer. A banded soil application of Ridomil has provided adequate control of Phytophtora without dinging germination.

Carrots are beginning to emerge from early April seedings, and the barley nurse crops are nearing 2 inches.

Transplanted sweet onions are rooting and putting on new growth. Goaltender can be used before weeds emerge within two days of transplanting and also after weeds emerge and onions have at least one leaf, but you are limited to 1 pint per acre per season. If using Goaltender as a pre-emergent, use the 8 ounce per acre rate. This limits a post-emergence rate to 8 ounces to stay under 1 pint per year.

Depending on your problem weeds, MSU weed specialist Bernie Zandstra suggests a different pre-emergent option, such as Prowl H2O, Outlook or Nortron, which are strong on grasses and some small seeded broadleaves. Then, save Goaltender at a full 16 ounces per acre rate for later in the season, which is more effective on more broadleaf weeds with up to four leaves. However, note that Goaltender has a 45-day pre-harvest interval when applied as a post-emergent and is not labeled for green onions.

Heated hoophouse tomatoes are nearing harvest in the earliest plantings. Some roots infected with Pythium have been submitted to MSU Diagnostic Services.

Tomato transplants are still going in across the region. Friday morning, May 11, is predicted to get down into the high 30s across our region. Frost will be likely in the northern Lower Peninsula, but low spots in the southern lower may also dip close to freezing.

Meetings

The 2018 MSU Weed Day is tentatively scheduled for July 27 from 8 a.m. to 3 p.m. on MSU’s campus. For more information, see the Weeds Day 2018 webpage.

Need your water tested for the Food Safety Modernization Act (FSMA)? Check out the Michigan Ag Water Lab Map.

Please contact me at phill406@msu.edu or 616-901-7513 with questions, concerns or to schedule a farm visit. You can also send plant materials to MSU Diagnostic Services.

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