East Michigan vegetable regional report – June 8, 2016
Good weather for planting has increased activity across the region. Some harvests are starting for early markets.
Weather
We are experiencing cooler than normal temperatures this week, and many areas in Michigan’s Bay and Thumb area received at least a quarter of an inch of much-needed rain over the weekend. The Saginaw Prairie has not been as fortunate, and everyone is hoping for rain this weekend. Our best chance is Friday night or Saturday, June 10-11.
See the table at the bottom of the article for rainfall (inches since April 1) and degree-day (base 50 degrees Fahrenheit since March 1) accumulations to date from Michigan State University Enviro-weather stations in the region.
Crops
Greenhouse tomatoes are just hitting the Green Thumb Auction. Other greenhouse tomato operations are in various stages. Indeterminate types are getting close to 5 feet at some operations, and determinate types are nearly 50 inches tall in bag culture systems. I haven’t heard many reports of disease incidence, but I have seen a number of flowers stuck on the ends of tomato pistils. Gray mold often starts on old tomato flowers and spreads to tissues where the flowers have fallen. Sometimes they get stuck in the crotch between stems and an infection starts there. Other times they stay on the ends of the tomato and start an infection there that looks like blossom end rot.
It is getting close to the time when sides should be roll up on hoop houses. This cross-ventilation will help jostle some of these flowers loose.
Sweet corn is knee-high where plastic was used, and harvest can be expected in some places by July 4.
Reports of Colorado potato beetle are just starting to show up in potatoes, tomatoes and eggplants.
Onion thrips have started showing up in seeded onions at the two- and three-leave stage. Movento with a surfactant is the best product for early season control, but it only makes economic and biologic sense when there are enough thrips to justify a spray. The threshold is one thrips per leaf, not one thrips per plant. You should keep count of the number of individual leaves when scouting. You can find an example of a summer spray rotation based on scouting in the MSU Extension article, “Cost-effective onion thrips control program 2: Apply at right time based on scouting and thresholds.”
MSU Extension fruit educator Bob Tritten finds strawberry harvest has just started in the last few days for farms in the southern parts of our region, and farms further north will open this coming weekend. Berry size for second and subsequent pickings is reduced where not enough irrigation was applied the week after bloom when berry cell division was occurring. These farms may have decent berry size for the first picking, but then it will decline rapidly. Tritten recommends light nitrogen applications of urea at many farms this season to overcome the lack of new growth in weak and discolored plantings.
Please contact me at phill406@msu.edu or 616-901-7513 to grab any suspected disease samples from your farm, or send the diseased plant parts to MSU Diagnostic Services.