OSU Extension Fruit & Vegetable Report – July 6th, 2024

 This edition of the OSU Extension Fruit & Vegetable Report was written using field observations and expertise from the following OSU Extension staff: Mark Badertscher, Thomas Becker, Chris Galbraith, Melanie Ivey, Carri Jagger, Matt Kleinhenz, Ashley Leach, Gigi Neal, Francesca Rotondo, Sabrina Schirtzinger, Ryan Slaughter

Vegetables

With periods of hot, intense weather so far this season, there have been reports of heat stress in transplants and in hoophouse crops. It is during times like these that managing temperatures in high tunnels becomes of great importance. It can pay to be proactive and utilize strategies for cooling your hoophouse before symptoms appear in your crop. Consider the specific crop, its growth stage, whether it is fruiting vs. non-fruiting, its temperature tolerances, and other factors when determining whether to apply shade cloth, vent the tunnel, or take other measures. Dr. Matt Kleinhenz of the OSU Vegetable Production Systems lab recently gave a lecture on the topic of high tunnel temperature management – check it out at the following link:https://www.youtube.com/watch?v=9dZyPo7Itv4

Squash bugs and squash vine borer are out and feeding. Squash bugs do not seem to be much of an issue yet in some areas. Striped cucumber beetle populations are high and reaching threshold in watermelons and other crops. Some organic growers have been using kaolin clay to prevent cucumber beetle feeding. Kaolin clay can also be applied to black plastic mulch during hot spells in order to cool down the microclimate and reduce heat stress in transplants. Cucumber downy mildew has been found in Ohio. Flea beetle defoliation is being seen in cole crops.  Diamondback moth larvae,  imported cabbageworm, and other caterpillars are out and feeding. Heat blistering on tomato stem tissue was reported during the recent period of extreme heat. There is very high thrips pressure in some pepper plantings. Japanese beetle, slug, and vertebrate wildlife damage is also being reported in various vegetable crops.

Flea beetles can be voracious pests of cole crops, leaving shot hole patterns in leaves. Photo by Chris Galbraith, OSU Extension. 

Fruit

Many abiotic disorders related to the unusual weather have been coming into the diagnostic lab this season. Wooly apple aphids have begun moving out on tender new growth. Diazinon, one of the chief crop protection products for this pest, is no longer being manufactured so control is more of a struggle. Oriental fruit moth populations are peaking. Bacterial leaf spot is being reported in peach. Powdery mildew is also being observed in apples, grapes, and peach.

Bacterial leaf spot can be a severe disease of stone fruits. Photo by U. Mazzucchi, Università di Bologna, Bugwood.org.

Blueberries have been hitting their peak in harvest, around two weeks ahead of normal this year. The strawberry season was reported to be poor this year – berries did not size up well and plants were not as vigorous this season on some farms. 

For more information or if you have questions, please reach out to a member of the Fruit & Vegetable team or your county extension educator.