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Richard Smart to Visit Hort Research Center on June 25

Improve Canopy Management and Reduce Disease with Dr. Richard Smart

The University of Minnesota and SMWGA will be hosting world renown viticulturist Dr. Richard Smart for a seminar, "Improved Canopy Management and Trunk Disease Implications for the Midwest" on June 25th, from 3-5pm at the UMN Horticultural Research Center. The seminar will be followed by a meet and greet reception from 5-6pm with Dr. Smart, featuring Minnesota wine and appetizers.

Dr. Richard Smart

To register: The event is $35, or $30 with a SMWGA membership. Please pre-register for this workshop in order to help us account for refreshments and seating. To RSVP, call or email Lisa Smiley at 651-492-5393 or

The event will take place at the Horticultural Research Center, 600 Arboretum Blvd, Excelsior, MN.

About Dr. Richard Smart: 

With over 40 years of experience consulting with viticulturists and winemakers around the globe, Dr. Smart is a global leader on vineyard management techniques. He is also the author of the book Sunlight Into Wine, viticulture editor of The Oxford Companion to Wine, and co-developer of the Smart-Dyson Trellis system. He has worked extensively to study and communicate how canopy management practices impact wine quality and yield, as well as how changing climates may impact the global wine industry into the future. 

Publish Date: 
Tuesday, May 22, 2018 - 9:00am

Learn to Plant a Vineyard with First-Hand Experience

Have you been thinking about starting a vineyard or a small grape planting? The best way to learn what it takes to start a vineyard is to help out at another established vineyard. However, these opportunities do not come along every day.

Fortunately, The Winery at Sovereign Estate is planting a new vineyard on June 16 and is offering free lunch and a viticulture class in return for helping to plant grapevines for a couple of hours! It will be a great learning opportunity for the beginner vintner, hobby grower, or someone looking to brush up on their skills before expanding their current vineyard. Details:

Vineyard Planting Outing – You’re Invited!

The Winery at Sovereign Estate and the University of Minnesota Extension viticulture program would like to invite you to a free vineyard planting outing.

Saturday, June 16th from 8:00am-2:00pm

The Winery at Sovereign Estate

9950 North Shore Road, Waconia, MN 55387

Start with a “classroom” lesson from the U of M’s Extension horticulturist, Annie Klodd, who will describe site selection, soil preparation, planting orientation, and planting…of course.

Then, put that new knowledge into action and head to the field where you will get to experience planting a vineyard of Marquette vines

Please RSVP by clicking the link below


Or email

Lunch and refreshments will be provided. Bring gloves and dress for the outdoors.

Hope to see you there!

Publish Date: 
Friday, May 18, 2018 - 1:15pm

Minnesota Research in the News

Dr. Richard Smart Monday June 25 at the Arboretum


Dr. Richard Smart:

Improved Canopy Management and Trunk Disease Implications for the Midwest


You are invited to a seminar and meet & greet with Richard Smart, global leader on vineyard canopy management techniques and author of Sunlight into Wine.

Dr. Smart will be speaking at the Minnesota Landscape Arboretum on Monday, June 25 from 3-5pm. A wine reception and refreshments with Dr. Smart will follow from 5-6pm. Registrations required. Clicke below to see the full flyer.

PDF icon Learn More Here!


Publish Date: 
Wednesday, May 16, 2018 - 4:30pm

Grapevine Pruning and Vineyard Prep Workshop April 21


Grapevine Pruning and Vineyard Prep Workshop

Get ready for the 2018 season with the Southern Minnesota Wine Grower Alliance and University of Minnesota Extension!

grape vineyard pruning cuttings on ground in pile

Visit the vineyard of Keith and Lisa Smiley to learn best practices for pruning vines on VSP and high cordon, managing winter injury, and choosing between training systems. Then get hands-on experience taking soil samples and evaluating vineyard health.

When: Saturday April 21, 10:00am-noon

Location: 10500 310th Street Way, Cannon Falls, MN 55009

Cost: $10/person


Annie Klodd, U of MN Extension Educator-Fruit and Vegetable Production

Lisa Smiley, Executive Director, Southern MN Wine Grower Alliance

Coffee and donuts included!

To register, contact Lisa Smiley at or 651-492-5393. You can also register at the event starting at 9:30am. Registration is $10/person. Make checks payable to SMWGA. Checks can be mailed to 10500 310th Street Way, Cannon Falls, MN 55009.

Getting to the vineyard: 10500 310th Street Way Cannon Falls, MN 55009 (Google maps link)


UMN Extension

Publish Date: 
Thursday, April 12, 2018 - 3:30pm

Clink! Sip + Savor Wine Market

Explore locally produced Wines and Food at clink!  UMN Grape Breeding and Enology staff will have a booth and will present a short talk at 4pm!

Clink Sip & Savor WIne Market 2018

Publish Date: 
Thursday, April 12, 2018 - 4:15pm

Bud Survival Data 2017-2018

Preliminary bud survival data has been collected and presented for key UMN and other cold-hardy varieties. 

Publish Date: 
Tuesday, March 20, 2018 - 11:15am

Potential bunch stem necrosis in Minnesota grapevines

Annie Klodd, Matt Clark, and John Thull

We have heard multiple reports of severe cluster necrosis, particularly on Marquette grapes in 2016 and 2017 in Minnesota, including here at the U of MN Horticultural Research Center. In some vineyards, it has caused substantial or complete crop loss.

Growers report that the clusters rapidly shrivel and die during veraison, while the plants and clusters appear healthy up until this point. It does not appear to be caused by black rot, mildew or botrytis. The rachis on the clusters desiccate first, followed by the berries.

This problem is still undiagnosed, however we recognize potential causes that are consistent with these symptoms. We are currently investigating it to determine the causes and extent, in order to develop appropriate management recommendations.

Knowing the number and geographic range of vineyards affected will help us address the issue most effectively. If you have experienced cluster necrosis in Marquette or another cultivar, we welcome you to contact us at

bunch stem necrosis

Berries beginning to shrivel following desiccation of the rachis and pedicels, in cultivar 1098. Photo: John Thull.

One potential cause - Bunch Stem Necrosis

While the issue is currently undiagnosed, one potential cause could be a physiological grapevine disorder called Bunch Stem Necrosis (BSN). It is not a pathogen or pest problem, but rather a disorder within the plant that is caused by environmental factors. It has been documented in many different cultivars including but not limited to Cabernet Sauvignon, Riesling, Himrod, Marquette, and some experimental hybrids.

Symptoms of bunch stem necrosis

The symptoms of BSN can occur during bloom, or during and after veraison. During bloom, pedicels darken and die, causing the flowers to fall to the ground. At veraison, BSN first appears as small, dark lesions on the rachis and pedicels (stem sections of the cluster). As the lesions expand they desiccate the pedicels and rachis, causing the berries to shrivel and die. 

Bunch stem necrosis forming

Necrosis beginning to develop on cultivar 1098. The rachis and pedicels have darkened and desiccated, and the attached berries are beginning to shrivel. Photo: John Thull, University of Minnesota.


bunch stem necrosis on red grapes

Bunch stem necrosis symptoms include dark, desiccated stems (rachis) followed by shriveled berries. Photo: Lorraine Berkett, University of Vermont.

Causes of Bunch Stem Necrosis

There are several potential causes of BSN, and they vary between individual vineyards. There is no known pathogen or insect pest associated with BSN. Rather, it is a plant physiological disorder that appears to occur following certain environmental stresses. Below are some of the possible causes of BSN based on previous research around the world. These differed between studies, vineyards, and years:

  • Magnesium (Mg) or calcium (Ca) deficiency2
  • Nitrogen deficiency or toxicity1,5
  • Heavy and irregular rainfall during veraison3
  • Below-average temperatures before bloom3
  • Standing water, and “wet feet” combined with heavy soil have also been proposed


More research is needed to determine the best management practices for bunch stem necrosis in Minnesota. Management will likely depend on the root cause of the issue at the site. Some studies have found that applying Mg and Ca as a soil fertilizer or foliar spray may alleviate BSN symptoms.2,4 but these results were inconsistent across instances, with other studies finding no effect. In some cases, altering pruning intensity has been found to reduce BSN.3

To address the recent necrosis issue in Minnesota and develop regional management recommendations, we hope to confirm whether the issue is BSN or another problem; narrow down the causes; and evaluate the effectiveness of various management options.


  1. Capps ER and TK Wolf. Reduction of bunch stem necrosis of Cabernet Sauvignon by increased tissue nitrogen concentration. Am. J. Enol. Vitic 2000. 51(4): 319-328.
  2. Cline RA. 1987. Calcium and magnesium effects on rachis necrosis of interspecific hybrids of Euvitis grapes cv. Canada Muscat and cv. Himrod grapes. Journal of Plant Nutrition 10: 9-16.
  3. Holzapfel BP and BG Coombe. 1995. Incidence of grapevine bunchstem necrosis in South Australia: effects of region, year and pruning. Aus. J. Grape and Wine Res. 1(1): 51-54.
  4. Jackson DI. 1991. Environmental and hormonal effects on development of early bunch stem necrosis. Am J Enol Vitic. 42: 290-294.
  5. Keller M and W Koblet. 1995. Stress-induced development of inflorescence necrosis and bunch-stem necrosis in Vitis vinifera L. in response to environmental and nutritional effects. Vitis 34(3): 145-150.
Publish Date: 
Tuesday, February 20, 2018 - 5:15pm

2018 UMN Research Update

Please plan to attend the 2018 Grape Breeding and Enology Research Update on Saturday, March 17 in conjunction with the Cold Climate Conference. 

For this year only, graduate students and researchers will present their findings and updates on ongoing projects at the conference hotel.  There is no charge to attend the research update, but please register and make a selection if you would like to stay for lunch ($25). Attendees will also have free access to the CCC Exhibit Hall on Saturday.

    Saturday, March 17th. Registration begins at 8:45 AM
    Session: 9:00 AM - 11:00 AM
    Lunch: 11:00 - 12:15 PM Exhibit Hall
WHERE: DoubleTree by Hilton, Bloomington, MN


      Lunch - $25   If you are not attending the Cold Climate Conference, but would         like to join us for lunch in the Exhibit Hall.

      No Charge  If you attend only the U of M Viticulture Update from 9:00 - 11:00

  Free parking available at the DoubleTree.


Publish Date: 
Tuesday, February 20, 2018 - 8:00am

UMN Extension Welcomes Annie Klodd

Annie Klodd Extension EducatorAnnie Klodd joined the University of Minnesota Extension in January as the new Assistant Extension Professor for Fruit and Vegetable Production. Her extension program will center on supporting Minnesota growers and improving fruit and vegetable production practices at both the commercial and home scales. She is excited to work with Minnesota grape growers and views viticulture as an important part of her program.

Annie is originally from Indianola, Iowa where her family owns a commercial vineyard and winery. She started working in the vineyard in 1997 when her family planted their first grapes, and also loves introducing customers to Midwest wines. She continued to work in viticulture as a graduate student at Penn State University, studying how perennial cover crops can be used to manage excess vine vigor. Most recently, she worked for Penn State Extension and led a national outreach program on integrated weed management. She is delighted to be returning to the Midwest horticulture industry!

Annie is conducting a needs assessment and wants your input. Along with collaborators Matt Clark and Brigid Tuck, Annie would like to capture a snapshot of the history of the grape growing and wine industry in Minnesota to help develop effective programming and to promote the industry going into the future. Come meet Annie at the MGGA Cold Climate Conference!

Fill out the brief questionnaire here.

What topics or issues would you like to learn about? Would you rather gather information through webinars, vineyard tours, study circles, newsletters, seminars, or something else? Do you have burning questions from the vineyard that would make for an interesting research topic? Here’s the link again, please tell us what you think.

Publish Date: 
Tuesday, February 6, 2018 - 8:15am


Registration is now open for the 9th Annual International Cold Climate Wine competition. Click on the logo to learn more.


Winter is Minnesota can be one of the most challenging times for the grape plants.  It's the main reason V. vinifera varieties aren't grown here.  Learn a little bit about whats going on in the vineyard in winter.

Wine making is a rewarding career, but is not free from headaches. A wine maker's nightmare is the re-fermentation of sweet wines and the instability of some wines. This blog entry addresses the topic and offers some strategies to avoid and mitigate a potential devastating re-ferment.


Are you curious if your wine is finished with malolactic fermenation? Here is a quick reminder on how to test with paper chromatography





ALERT: September 27, 2016. Spotted Wing Drosophila (SWD) in Grapes: A short memorandom on SWD in Minnesota and associated volatile acidity. Read more here

Fall vineyard managment should focus on managing insects, vertebrate pests, rots, and diseases that will impact the vines in the next growing season.  Making quality wines requires disease intervention and sorting, as infected fruit will impact wine quality. Read more here.


International Cold Climate Wine Competition 2016 Results here!

Northern Grapes Project Webinar Registration

“From Vine to Glass: Understanding the Flavors and Aromas of Cold-Hardy Grapes and Wine”
Tuesday, May 17th*, 2016
12:00 Noon Eastern (11:00 am Central)
7:00 pm Eastern (6:00 pm Central)
*Please note this is a date change from the original date of May 10th.

Join Anne Fennell of South Dakota State University, Adrian Hegeman of the University of Minnesota and Somchai Rice of Iowa State University as they discuss their research conducted on Marquette and Frontenac as part of the Northern Grapes Project. 

Mock Winery Inspection

Friday April 29, 2016


Savor Minnesota

This Saturday April 16, 2016


Itasca Grape Vine Named

The University of Minnesota releases its news wine varieity 'Itasca' on April 4, 2016


Intergeneric Grafting

Experimenting with different grafting techniques including grafting Ampelopsis with a hybrid rootstock.

Preliminary Bud Survival Data

Early bud chop counts on cold-hardy cultivars at the HRC


Old blog entries

Are you looking for previous blog posts? Search the archived entries