Southwest Michigan vegetables regional report – July 10, 2013
Insect activity has increased greatly over the past two weeks in southwest Michigan.
According to Michigan State University Extension via Enviro-weather, temperatures over the past two weeks at the Southwest Michigan Research and Extension Center averaged near normal with highs from 73 to 86 degrees Fahrenheit (average is 81 F) and lows from 55 to 71 F (average is 58 F). We are at 1,209 base 50 GDD, which is slightly ahead of normal, but much behind the 1,585 of 2012. The area received 2 to over 4 inches of rainfall during the period.
The biggest change over the past two weeks has been an increase in insect activity. Mites, thrips, tomato hornworms, tarnished plant bugs, Colorado potato beetles and cucumber beetles can easily be found. I have not caught squash vine borers in my traps at this time, but it is close to when they should appear, so protection is probably needed.
Tomatoes grown in low tunnels are close to harvest. Those in early planted, non-tunneled fields have 1.5 inches in diameter fruit. The crop continues to look good in response to favorable temperatures. Peppers and eggplants are doing much better in response to warm temperatures. Pepper plants have 2 to 2.5-inch fruit.
Yellow squash, zucchini and cucumber harvest continues. Harvest volume has increased as more fields come into production. Watermelon has baseball-sized fruit and some growers are having plant wilting issues in the poorly drained areas of their fields. The exact problem has not been identified at this time.
Sweet corn from under row covers is close to harvest. Early planted, non-covered fields are silking.
Early planted potatoes are in bloom and the rows have filled in. Earliest fields have tennis ball-sized tubers.
I continue to receive reports of herbicide drift damage. Growers with field crop neighbors should warn them about how sensitive vegetables are to certain herbicides and have them take the necessary precautions during application.