West Central Michigan vegetable regional report – May 18, 2016
Crop progress has been ongoing but slow in west central Michigan.
The National Weather Service has issued a frost advisory for Oceana, Newaygo and Mecosta counties through tomorrow morning, May 19. Michigan State University agricultural meteorologist Jeff Andresen indicated this will likely be a patchy frost confined to low-lying areas.
Asparagus harvest was slow but ongoing Monday, May 16, in Oceana County. Three Oceana County growers I visited did not report any frost or freeze damage over the weekend.
Carrot stands continue to develop in Oceana County, with light showers helping create good conditions for carrot emergence and growth.
Cucurbit planting had not started in Ottawa County as of yesterday, May 17. The pre-harvest interval has been shortened to 14 days via a Supplemental Label for the herbicide Sandea on cucumbers, cantaloupes, honeydews and Crenshaw melons. Growers can download the Sandea Supplemental Label or read more about it at “New Sandea Supplemental Label reduces pre-harvest interval on cucumber” by Michigan State University Extension.
For cole crops, cabbage maggot egglaying is expected to peak in the next week based on degree-days from the Hudsonville, Sparta and Standale/Walker Enviro-weather stations. This will be the peak risk period for this pest.
Onion stands are reported to be developing well in Ottawa County. Onions had one true leaf with a second developing at one location. Herbicide application including gramicides for barley covers was finished or ongoing. There has been a recent report of onion maggot damage in Michigan onions. This pest feeds below ground, causing young onions to wilt and die.
Potato planting is about 30 percent complete for chipping varieties in Montcalm County.
Tomato growers should start weekly copper applications after transplanting to prevent bacterial diseases including bacterial speck, spot and canker. Please report outbreaks of these to your local MSU Extension vegetable educator, as work on resistance is ongoing. Recent work has detected copper resistance from some populations of bacterial speck and spot, but not canker. Because canker can be a serious problem, copper is still recommended. In early July, assess if you have bacterial disease symptoms; if none are present, copper can be discontinued. Take action now to kill volunteer potatoes, which are the only way late blight can overwinter in Michigan. Killing them now could pay off later.
Sweet corn had emerged at one Ottawa County location I visited yesterday, May 17. Reports from a grower in southwest Michigan suggest corn is slow growing and yellow; warm temperatures should speed growth soon.