Fruit and Vegetable News

Natalie Hoidal & Marissa Schuh   August is almost here, and with all of the rain and humidity, plant diseases are quickly catching up right as peak summer harvest season begins. This week's update includes an overview of recovering from storm damage, keeping our lungs healthy in smoky air, and crop updates which heavily feature plant disease problems.  Helping plants recover from severe storms Strong storms across the state earlier this week caused flooding, hail damage, and wind damage on many farms. If you had areas that flooded, crops that were touched by floodwater shouldn’t be harvested and sold. Flood water is different from pooling rain - use your discretion if the water in your field is just from rain that is pooling on the surface. If flood water moved from elsewhere on your farm into the field, avoid selling produce that touched this water. Weather was conducive for many diseases before the severe weather, and looking ahead, while things will cool down, many di...

Article written by Madeline Wimmer, Extension Educator - Fruit Production Apples: About: Honeycrisp sport varieties Grapes: Vine nutrition: Veraison is the next opportunity for petiole sampling Apples: Images: David Bedford, UMN researcher who is renowned for his work breeding apple varieties like Honeycrisp, spoke at the 2025 Minnesota Apple Growers Association summer tour about the difference between an apple sport and true cultivated variety. This topic led into more discussion about various Honeycrisp sport varieties, including Premier Honeycrisp™ and Royal Red Honeycrisp™. About: Honeycrisp sport varieties The Honeycrisp (MN 1711) apple variety has been around for nearly 35 years, and continues to be a favorite apple for many consumers. While consumers know and love the fruits for their crisp texture and balanced flavors, most growers are familiar with some of the challenges that come with growing the tree itself: biennial bearing tendencies, with fruits prone to bitter pit a...

The University of MN/University of NH High Tunnel Cover Crops Trial is recruiting organic high tunnel growers to receive cover crop seed and participate in cover crop planting in fall 2025 or spring 2026. Our project aims to enable organic high tunnel growers to reduce their dependence on purchased composts and manures by using nitrogen-fixing legume cover crops.   Participating farmers will receive seed of "best bet" legume cover crops for your chosen timeslot, as well as a free soil test. To learn more about participating in the trial, please fill out our interest form . We will also be holding an informational webinar for farmers interested in taking part in the trial on Monday, August 18 at 12pm CDT on Zoom. Sign up for the informational webinar here. Upcoming planting timeslot options are:  Fall/overwinter cover crops (planted between August 15 and November 1), which will overwinter and be terminated before your spring vegetable planting. Early spring cover crops (pl...

Natalie Hoidal & Marissa Schuh Much of the state is under water as we write this update, following torrential rain storms across Minnesota on Wednesday. Wet fields and air quality alerts followed by hot, humid weather this weekend likely mean less time in the field for a couple of days. Next week is supposed to bring drier, cooler weather, just in time to harvest any remaining garlic and plant final successions of fall crops like carrots and broccoli. “Farm hacks” While many of our readers are experienced farmers, we know plenty of our readers are just getting started. There are simple “hacks” that may seem obvious to folks who have worked on or visited their fair share of vegetable farms, but are not necessarily intuitive. For the next couple weeks, we’ll highlight some “farm hacks” that save farmers time and money. It’s hard to think about irrigation right now after months of heavy rain, but we often see hot dry spells in August, and it’s good to be prepared. This week we’re foc...

Article by Madeline Wimmer-UMN Extension Educator, Fruit Production General fruit : About: The winsome fly and Japanese beetles Pollinator installations and support Apples: Growth update: Beginning of ripening Grapes: Symptom check: Black rot on grape berries Plums: Russeting on fruits General fruit: About: The winsome fly and Japanese beetles Image: Japanese beetle adults will continue to feed as winsome fly eggs are laid on their thorax (middle body segment). The larval feeding eventually kills the Japanese beetle, which disrupts egg-laying in female beetles. While you’re out monitoring for and managing Japanese beetles this year, you might take note if you see any beetles with one or more white dots on their green thorax. These are eggs of the winsome fly ( Istocheta aldrichi ), a tachinid fly that is a parasitoid* of Japanese beetles. It only takes a few days after eggs are laid for a larva to hatch and begin feeding and developing through its larval stages. This damage does not ca...

Article written by Madeline Wimmer - Extension Educator, Fruit Production Images: Pollinator resources often recommend planting at least three species of pollinator friendly plants, specific to your crop and region, for each bloom period (early, mid-season, late). Introduction Successful pollination is key for quality fruit production anywhere in the world. When the fruit set is lower than expected, there are a number of factors that could be contributing, depending on which fruit crop you’re growing, including the following:  Very few fruit crops, like grapes, are wind pollinated, but the majority of fruit crops rely on, or benefit from insect pollination (primarily bees). Some fruit crops are self-incompatible, which means they will not use their own pollen for pollination. Two varieties used to cross pollinate one another need their bloom times to overlap. Additionally... Certain fruit crops, like honeyberries, are self-incompatible and will not accept pollen from varieties tha...

We are hosting two high tunnel field days at the University of Minnesota's St. Paul Campus. August 7, 10am - 12pm: Managing high tunnel insects & diseases + Postharvest handling and food safety Scout for insect and disease issues in the high tunnel, and then get hands-on experience harvesting, grading and packing cucumbers, tomatoes, and peppers for wholesale markets. Learn about washing setups, food safety and how to increase shelf life, safety and quality. Led by Marissa Schuh, Annalisa Hultberg, and Ariel Pressman.  Image: Canva.com   September 2, 10am - 12pm: Preparing your high tunnel for winter: flipping beds and planting a winter cash crop or cover crop Practice (hands-on) cleaning up beds after a cash crop, and prepping the soil for the next crop. Learn about cover crops that perform well in high tunnels (free seed may be available!), and winter cash crops like spinach that can be grown in unheated Minnesota high tunnels. Led by Natalie Hoidal, Adria Fernandez, and...

Article written by Madeline Wimmer - Extension Educator, Fruit Production Apples : When should trunk guards be removed from apple trees? Check bands, fasteners, and clips to prevent girdling Grapes : Seasonal update from the UMN HRC Kiwiberries : Update and about: UMN kiwiberry research and breeding efforts Apples When should trunk guards be removed from apple trees? Images: Two pictures showing tree guards on older trees. One is installed on a central leader trained tree (left) and the other on high-density trained tree (right).  Trunk guards are helpful for apple tree establishment, as they protect against damage from wildlife and herbicide sprays. But when is the appropriate time to remove them, and what are the consequences of leaving them on too long? Depending on tree vigor, site conditions, and wildlife pressure, guards can typically be removed once trees are no longer at risk for damage—but they should be checked periodically. Prolonged use of tree guards can be problematic...

Natalie Hoidal . Marissa Schuh , & Charlie Rohwer After a week of poor air quality, some extremely hot days, and then a downpour, the week ahead is looking like it will be lovely for catching up on field work. Most plants are thriving with the heat and regular rainfall, and we’re entering the exciting and intensely busy part of summer where farmers are planting, maintaining, and harvesting all at once.  Farm Hacks While many of our readers are experienced farmers, we know plenty of our readers are just getting started. There are simple “hacks” that may seem obvious to folks who have worked on or visited their fair share of vegetable farms, but are not necessarily intuitive. For the next few weeks, we’ll highlight some “farm hacks” that save farmers time and money.  Pick your own: we mostly think of berries and pumpkins when we think of pick your own crops, but there are plenty of vegetables that just make sense as pick your own veggies rather than farmer picked veggies. Gr...