Fruit and Vegetable News

Madeline Wimmer- UMN Fruit Production Extension Educator This fruit update contains information about… Apples - San Jose scale at the UMN Horticulture Research Center (HRC). Grapes - Black rot and Japanese beetle sighting at the UMN HRC. Minnesota Department of Agriculture IPM Fruit Update sign up form. Apples San Jose scale at the UMN Horticulture Research Center (HRC) Images: 1) An apple branch wrapped with reversed electrical tape within a population of San Jose scale (Diaspidiotus perniciosus), 2) using a jeweler’s lens to look closely, and 3) a magnified view of San Jose scale crawlers, which are the small yellow specks mixed among a cluster of scale coverings. Images taken by Kate Scapanski, UMN apple researcher at the UMN Horticulture Research Center (HRC.) Scale insects are unique in their appearance and life cycle. To the untrained eye, they can look like lichen or rough bark, but their strange shell-like structures are actually an exudate that houses a soft-bodied insect unde

Authors: Marissa Schuh , Shane Bugeja , and Natalie Hoidal General Notes This was the week where plant diseases made themselves known across Minnesota. Specifics will be discussed below, but key things across all crops is… Stay out of fields when leaves are wet Prune and stake relevant crops to improve airflow so leaves dry out Manage weeds within and on field borders to increase airflow Scout regularly – the earlier you catch the disease, the more effective your management can b Drowned out areas in fields need to be closely watched for weeds as the water recedes. Pre-emergent herbicides may have been degraded or washed out, and their performance can be subpar. Late emerging pigweeds, such as waterhemp , can make a quick deposit into your weed seed bank if not caught soon enough. Cultivation is also an option to control these plants, but be mindful of the risks to your farm’s soil health from repeated passes. If the land is not going back into vegetable production, consider sowing

Marissa Schuh, IPM Extension Educator, mschuh@ umn.edu Tomato might be the spottiest vegetable we grow – there are many diseases that can cause leaf spots, and they can all look very similar. Some of the diseases are caused by bacteria, some are caused by fungi. This means that some of the same cultural practices may work, but if you are thinking about chemical controls and longer term management, knowing which pathogen you have will be important.   Early blight attacks the oldest leaves first. Photo: Gerald Holmes, Strawberry Center, Cal Poly San Luis Obispo, Bugwood.org Fungal pathogens We have two fungal diseases we commonly see causing leaf spots in Minnesota – early blight and septoria leaf spot. Early blight is very common. The pathogen survives in crop debris and weeds, then infects plants by splashing up into the foliage. This means that the first part of the plant infected is the oldest leaves. Infected leaves develop brown spots, and if you look closely at these spots, the

Marissa Schuh, Horticulture Integrated Pest Management extension educator Thinking about scaling up your vegetable production? Curious about cut flowers, weed management tools, or small farm cover crops? Want to connect with UMN researchers and extension educators? Sign up now to attend the Organic Fruit and Vegetable Field Day July 24 from 5-8 on the UMN St. Paul campus . Enjoy a free meal, tour university research plots, and network with other growers and resource people from the UMN. This event is free and will be interpreted, please register so we can make sure we have enough food and the right interpreters in place. For more information and registration, visit the event information page  or fill out the below form. Loading… Questions? Reach out to Marissa Schuh at mschuh@umn.edu.

The University of Minnesota and University of New Hampshire are partnering to conduct on-farm research about the performance of legume cover crops in organic high tunnel vegetable rotations in the Midwest and Northeast regions. The goal of this project is to enable organic high tunnel growers to reduce their dependence on purchased composts and manures by using nitrogen-fixing legume cover crops to support soil fertility, productivity, and sustainability. We are currently recruiting organic high tunnel growers to receive cover crop seed and participate in the on-farm research trials, which will begin in fall 2024 for overwinter cover crops or spring 2025 for spring/summer covers. We have two levels of participation available, so you can choose the level of commitment that works for you. Join us for an information session on Monday, June 24th at 11:30 CDT, or Tuesday, July 30th at 6:30pm CDT on Zoom. During the webinar, you’ll learn more about participating in the trial and have opportu

Madeline Wimmer- UMN Fruit Production Extension Educator This fruit update contains information about… Grapes - Growth stage, downy mildew symptoms, and second generation phylloxera issues. Honeyberries/haskap - General information, and Blue Fruit Farm field day with fresh honeyberry tasting panel. Blueberries - growth stage. Black currants - sawfly management. LINK FIXED: Minnesota Department of Agriculture IPM Fruit Update sign up form.   Grapes Image: Grapevine cultivar Madeleine Angevine in bloom at the UMN Horticulture Research Center (Zone 5a; photo taken by John Thull UMN HRC Vineyard Manager.) Downy mildew Images: 1, 2) Grape upper leaves showing symptoms of downy mildew (Plasmopara viticola) infection and 3, 4) grape leaf undersides showing downy mildew sporulation. Photos taken at the UMN Horticulture Research Center (Zone 5a) by John Thull, UMN HRC Vineyard Manager.) Downy mildew (Plamopara viticola) is one grape fungal pest that thrives in highly humid environments. It can

Madeline Wimmer- Fruit Production Extension Educator This fruit update contains information about… Apples - Growth stage, apple maggot monitoring and management, codling moth update, and Honeycrisp leaf mottling disorder. Grapes - Growth stage and a note about when to start basal leaf removal. June-bearing strawberries - Growth stage and diseases to watch out for during rainy harvest seasons, and fruit damage from insects and insect-like pests. Minnesota Department of Agriculture IPM Fruit Update sign up form. Apples Image: Connell Red apples ranging from 3-4 cm in diameter at Northwoods Apple Orchard located in Oronoco, Minnesota (Zone 5a.) Growth stage Apples in SE Minnesota are ranging from 2.5-4.5 cm in diameter this week in SE Minnesota. Insect pests Apple maggot Image: A map of Minnesota on 06/12/2024 showing southern regions where apple maggot adults are expected to emerge in 2-3 weeks. Image retrieved from the USA National Phenology Network. The USA National Phenology Network m

Authors: Marissa Schuh and Natalie Hoidal We've continued to have bouts of rain, but growers are still getting field work and planting done. Pest issues are on the rise, and we have our first few days of hotter weather on deck. General Notes Rainy weather and N deficiency The frequent and sometime heavy rains have led to nutrient deficiencies. Transplants are going in nutrient stressed in many spots after being held longer than anticipated, and rains have caused nutrient leaching. If plants are showing signs of nutrient deficiency, side dressing will be especially important this year. Quick release organic sources of N include blood meal and Chilean nitrate (check with your certifier before using this one, and be careful how you use it as it can burn roots). Nitrogen deficiency appears as uniform yellowing in leaves. Photo: Gerald Holmes, Strawberry Center, Cal Poly San Luis Obispo, Bugwood.org Deer We have seen some spots where deer have done significant damage to transplants.

Marissa Schuh , Horticulture IPM Extension Educator. Originally published June 7,2023, updated 2024. Growers are reporting seeing Colorado potato beetles and their eggs in field. We all know what these guys are capable of, let’s do a rundown of Colorado potato beetle management. The first flush of Colorado potato beetle activity is the emergence of overwintering adults, who feed and lay eggs. Photo:  Jack Rabin, Rutgers NJ Agric. Expt. Station, Bugwood.org. Non-chemical Controls Trials on Minnesota farms have found that flaming, trap crops, and trenching didn’t really work . Our old friend row covers can be helpful in protecting very small plants (assuming where you are planting isn’t full of plant debris that are housing overwintering adults).  Mulches seem to make it harder for adults to reach plants, and for larvae to bury into the soil to pupate.  Eggs can be squashed, and larvae and beetles can be removed from plants and killed in a variety of emotionally cathartic ways (soapy wa

Authors: Natalie Hoidal and Marissa Schuh . UMN Extension Educators. Reviewed and updated 2024. Cucumber beetles show up in Minnesota every year. This article provides a brief overview of cucumber beetles along with recommended management strategies you can use after your cucurbits are planted. Cucumber beetles: an overview Cucumber beetle, Gerald Holmes, Bugwood Striped cucumber beetles, Acalymma vittatum, are a common insect pest of cucurbits. While they are almost always present, in some years they are worse than others. Striped cucumber beetle overwinters as an adult, typically in debris or field margins near cucurbit plantings. They tend to become active in early June in the southern part of the state, and become active further north in mid to late June. As soon as cucumber beetles locate your cucurbit fields, they begin to mate and lay eggs at the base of plants. Larvae emerge underground and feed on plant roots, so they are not easy to detect until after they pupa

Annalisa Hultberg, food safety educator As you are busy planting and beginning early harvests, it is a good time to think through your food safety procedures to ensure you have safe, quality product this growing season. Here is a checklist for the early season to-dos to prepare your packing and washing areas for the season. 1. Deep clean the packshed  It is a good idea to do a deep clean of your packing area and all equipment in the early season. Disassemble postharvest washing equipment as possible, scrub surfaces with soap and water, and then apply a sanitizer like a bleach solution, focusing on the areas that will touch the produce directly. Don't forget walls, ceilings, coolers, floor drains, the outside and inside of equipment, and corners and storage areas to get rid of filth from the winter.   For more information on making a sanitizing solution for surfaces,  see this webpage.  Common sanitizers are bleach or a PAA - based sanitizer like Sanidate 5.0. You can get Sanidate f