Michigan State University Extension

Blueberry Newsletter - Blueberry Bites

View From The Field

Bluejay - Paw Paw

Bluecrop - Paw Paw

Bluecrop - Fennville

Pest Update: Insects

As fruit set begins and petals fall off, this opens up the calyx cup area where cranberry fruitworms lay their eggs. Many fields do not require control of this pest, but where these is a history of infestation issues with fruitworms, monitoring traps should be used for detecting pest activity and helping to time applications to protect berries from the larvae.

Pollinator Workshop - June 1 in West Olive, Michigan

The program will include a description of pollination practices at the host farms and results from recent research at these locations. Presentations will be by experts from the MSU Department of Entomology including Meghan Milbrath (honey bees) and Rufus Isaacs (blueberry pollination). The events will include a mix of hands-on demonstrations of sampling for colony strength, bee activity levels in the crop field, and pollination success. There are no RUP credits for this program. A sign up for June 1 will be available soon.

Mummy Berry

Disease Update

Mummy berry shoot strikes have been spotted throughout western Michigan, particularly in the southwest part of the state (photo). This is the secondary infection phase of the disease so if there are minimal shoot strikes within a field, softer products can be utilized (e.g. biofungicides) to help protect pollinators. Now is also a time where anthracnose fruit rot control is critical. The most effective fungicides are in FRAC codes 7, 9, 11, 12 and 29 and FRAC 11 fungicide resistance has been detected throughout Michigan. For resistance management, multisite fungicides like Captan, and Ziram are also good options as an alternative to site specific fungicides. Review these fact sheets for more information

Anthracnose Fruit Rot

Don't Guess, Test!

The diagnostic program supported by the Michigan Blueberry Commission (MBC) first piloted last year, is continuing in 2023. This program funded by the MBC will cover the diagnostic fees for up to two samples per Michigan blueberry grower. The samples will be evaluated and tested as appropriate by specialists in the MSU Plant & Pest Diagnostics (PPD) lab.  If there is anything concerning or puzzling in your blueberry field, be sure to take advantage of this opportunity.

Diagnostic Testing Form 

Horticulture Update

We head into another warm and relatively dry week. Much of what was mentioned last week about irrigation is also relevant this week. Irrigation is particularly important for newly planted fields, where plant root systems are still quite small. Blueberry plants won’t need as much water now as during fruit ripening, but this initial flush of vegetative growth will use some water to keep the soil moist and support strong root and shoot growth.  

With newly planted blueberries, now is a good time to consider slow-release fertilizer. This is especially important for new plantings with soils amended with wood chips or sawdust. Much of the nitrogen from most fertilizers will be bound by the chips or sawdust as it breaks down, so slow release will aid in preventing this. 

Irrigation is Necessary in Michigan Blueberries
Irrigating Michigan Blueberries

MBC Report 

On May 12th MBC members Denny Vander Kooi, Dave Reenders and Nancy Nyquist, Executive Director, attended an event on MSU’s campus with Senator Peters to learn more about SWD and his legislation to add resources for additional research. 

Samba Wasps - Michigan Farm News

Extension Update

The southwest fruit team hosts weekly IPM meetings feel free to join us in-person or virtually from 5:30-7 at the southwest Michigan Research and Extension Center. 1 RUP credit is offered each week. Sign up here!

Upcoming Webinar - June 6

Watch your email for sign-up information about an upcoming webinar on June 6. We will be covering insurance and pathogen updates during a short lunchtime webinar.

Upcoming Events




Pollinator Workshop - North

June 1,10 am - Noon

West Olive

Blueberry Season Update

June 6, 12-1 pm


Blueberry Bites is compiled by Cheyenne Sloan, Blueberry and Small Fruit Educator

Contributors: Rufus Isaacs, Tim Miles, Josh VanderWeide, Cheyenne Sloan

Questions? Comments?

MSUE Small Fruit Educators

Blueberry and Small Fruit Educator - Cheyenne Sloan

Small Fruit Educator - Carlos Garcia Salazar

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