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Showing posts from May, 2024

Test, don’t guess: Is foliar nutritional analysis right for your fruit crops this growing season?

Madeline Wimmer, UMN Extension Educator- Fruit Production & Soon Li Teh, Extension Specialist and Assistant Professor in Grape Breeding and Enology Image: a plant nutritional pyramid showing from bottom to top those nutrients supplied by air and water: Carbon (C), Hydrogen (H), and Oxygen (O); primary macronutrients: Nitrogen (N), Phosphorous (P), and Potassium (K); secondary macronutrients: Calcium (Ca), Magnesium (Mg), and Sulfur (S); micronutrients: Molybdenum (Mo), Boron (B), Nickel (Ni), Copper (Cu), Zinc (Zn), Iron (Fe), Chlorine (Cl), and Manganese (Mn).  Graphic created by Madeline Wimmer, 2023. Plant nutritional analysis—also known as foliar/leaf/petiole testing—is the practice of analyzing nutrition within a plant to determine adequate, excess, or deficient nutrient levels. Oftentimes, this involves collecting a plant’s leaf, leaf with petiole, or only the petiole at a specific growth stage. Plant nutritional analysis is a critical step in determining any potential nutrie

Weekly Vegetable Update - May 29, 2024

Author: Marissa Schuh Growers are plugging away with planting and other early season tasks in between rains. This May has been one of the wettest in recent years – quite a change of pace from the last few Mays we had. Our crops have moisture, but so do our plant pathogens We’ve gotten some questions about potential fungal diseases this week, which makes total sense – we’ve had rain, humidity, and dew. If this moisture keeps up, we will continue to see plant diseases show up. Some reminders on general practices that help prevent a wide range of pathogens… Work in field when they’re dry, especially if you’re pruning, tying, or staking plants Mulches between and within rows can reduce splashing and movement of some pathogens Increase airflow by using proper plant spacing, weeding, mowing field edges, and tying/staking Fertilize plants according to soil test and nutrient management recommendations Fungicides are most effective when used as soon as the disease is detected. Products don’t

Fruit update – May 29, 2024

Madeline Wimmer- Fruit Production Extension Educator This fruit update contains information about… Apples- growth stage and thinning; insect & disease management. June-bearing strawberries- growth stage, and disease management. Additional fruit growth stage highlights. “Wild,” non-domesticated fruits in Minnesota. Minnesota Department of Agriculture IPM Fruit Update sign up form. Apples Images: 1) Apples with 18-24mm fruits growing at Northwoods Apple Orchard in Oronoco, MN (Zone 5a.) 2) Minneiska (SweeTango®) growing beyond 16 mm and 3) aborted fruits, post chemical thinning at the UMN Horticulture Research Center (Zone 5a, pictures taken by Kate Scapanski, UMN Apple Researcher.) Growth stage and thinning Many apples are at or beyond 16mm in diameter within the southern parts of Minnesota. Just as I mentioned in last week’s update, fruits that have reached these sizes have limited chemical thinning options. Carbaryl and ethephon may still be used with less guaranteed efficacy for

Fruit update – May 22, 2024

Madeline Wimmer- Fruit Production Extension Educator This fruit update contains information about… Apples - growth stage, & insect and disease management Grapes - growth stage, canopy management, and insect & disease management, note on slime molds in the vineyard, and UMN online grape course. Black currants - about, growth stage, and currant borer management. Northeastern Minnesota fruit gallery Apples Images: 1) Minneiska (SweeTango®) fruits at 9-10mm in diameter, 2) Zestar!® fruits at 11.5-12.5mm in diameter, 3) an example of an apple thinning template, and 4) Minneiska (SweeTango®) fruit passing through the 9.5 mm hole on the apple thinning template; pictures taken at the UMN Horticulture Research Center near Chaska, Minnesota (Zone 5a; pictures taken by Kate Scapanski, UMN Apple Researcher.) Growth stage Similar to how bloom times vary, apple growth rates are not the same across varieties. Zestar!®, shown above, is on average ahead of Minneiska (SweeTango®) and is also kno

Weekly vegetable update – May 22, 2024

Authors: Marissa Schuh , Shane Bugeja , and Natalie Hoidal Much of the state got over an inch of rain Tuesday, with reports of over 2 inches of rain common across much of the state. General Crop Notes With ample moisture and moderate temperatures this spring, cool season grasses are having a blast. As cover crops such as cereal rye start to enter reproductive stages, the options for effective termination narrow. Roll-crimping is typically done after the boot stage, and is popular with some no-till organic producers. You can tell if your plant is in the boot stage by feeling the top of the stem for a bulge. That bulge contains the seed head of the plant. Later growth stages after boot are similar to wheat’s . Roll-crimping is not perfect. For example, a 2012 Iowa State University study needed 2 to 3 passes with the roll crimper to kill a hairy vetch/rye cover crop mix. Extra passes in the field are not ideal or cheap, especially with a busy season ahead. The upper half of a wheat pla

Food Safety and Disease Management Field Day at Apple Jack Orchards June 20

Annalisa Hultberg, Extension Educator, Food Safety Madeline Wimmer, Extension Educator, Fruit Production Join UMN Extension for a field day to learn new strategies to use good food safety practices and plant disease management strategies in your fruit and vegetable farms and orchards this summer. These practices can reduce the disease burden on your farm as well and protect your produce from unintentional contamination from human pathogens like E. coli or Salmonella that can cause illness. Date: June 20, 2024 10:00 - 1:30 Location: Apple Jack Orchards, 4875 37th St SE, Delano, MN 55328 Cost : $15 per farm, for up to two attendees. All registered attendees receive lunch and insect detection and food safety supplies. Registration : Register by June 18, 5:00 pm. .  Food Safety topics:  Learn best practices to manage human pathogens of concern on the farm which can contaminate your produce Mock GAP audit - what is a GAP audit, and how could it hel

First weekly vegetable update of 2024 - May 15, 2024

Authors: Marissa Schuh   and Natalie Hoidal A rainy spring has delivered much needed moisture, with the amount of the state in drought going from a majority of the state to limited areas in the Northwest/central and Southeast corners. What might we be in for the rest of this growing season? NOAA Climate Prediction Center's models for the summer call for hotter than normal temperatures and average precipitation. There are also predictions that we will have wildfire smoke on-and-off this summer, though for fewer days than last year. The Minnesota draught monitor at the end of 2023 (left) to May 7th. The darker the color, the more severe the draught in that area. Images: US Draught Monitor General crop notes Every spring we receive some photos of transplants that indicate over-watering. While some questions from beginning growers who are just getting the hang of things, some came from experienced growers as well. One of the most common causes is that a grower will try a new potting