Horticulture Update



The harvest season has slowed slightly compared to the beginning of the season, which has some producers picking mid-late cultivars sooner than expected to meet market demand. ‘Draper’ and ‘Envoy’ are approximately half-way through harvest, while first pick in most ‘Bluecrop’ and ‘Calypso’ fields are complete.  

We will have warm weather throughout most producing counties over the next week. It will be smart to increase irrigation in plantings that will experience temperatures above 85-90F, as plants use more water to maintain transpiration at high temperatures. A lack of water at high temperatures will limit berry size and yield. In some areas, it may be useful to use overhead irrigation to cool plantings; however, keep in mind that follow-up fungicide sprays will be needed to prevent fruit rot development. 



Although the fall planting season is still months ahead, I want to point out a few important results from our replanting survey that will be elaborated on in more detail later this summer and fall. Replanted fields that have struggled to grow tend to have a few horticultural issues, including a higher pH (~5.2), lower wood chip levels, and typically a single drip line (rarely two) compared to healthy replanted fields. Neither of these points are the sole cause of replanting issues, and there are others we will be exploring, but certainly each contributes and highlights the importance of the initial horticulture set up to the success of “replanted” plantings.    

Insect Update

Blueberry maggot activity continues in southern Michigan, and should be monitored to ensure fields are managed to protect from this insect. Monitoring traps for SWD in Van Buren, Allegan, and Ottawa counties are starting to show an uptick in the activity of this pest, so SWD management should be implemented in fields where there are ripe berries being harvested. We are also expecting this pest to start increasing in intensity due to the activity we are seeing in wild areas. Our sampling of wild hosts for SWD last week have indicated larvae developing in most of the ripe honeysuckle, black raspberries, etc. As these complete development and move into crop fields we are expecting greater activity of SWD that requires grower management. There are also reports of some hot spots where Japanese beetle is more active than in recent years. Most of the treatments for SWD or BBM will also control this pest, but there are also some cultural approaches (bare soil to reduce egglaying) and additional chemical controls (soil applied insecticides to control larvae) that can be considered. 



Pathogen Update

Rain this week will drive fruit rot diseases (I.e. Anthracnose Fruit Rot, Alternaria Fruit Rot and Botrytis Fruit Rot). Preventative fungicide applications can play a crucial role at this moment (e.g. FRAC codes 3, 7, 9, 11, 12, 17 and 29).  Please be mindful of preharvest interval on various products. Also timing irrigation practices to coincide with natural dew formation is important.  During harvest, remember to harvest fruit quickly and ideally under dry conditions. Also, once fruit has been cooled, ensure that it remains cool during shipment/delivery. Sharp rises in temperature will cause significant moisture to form on fruit. 

Finally, we have been observing more stress in newer plantings, it is important to remember to keep these young plantings well-watered and to look for signs of shoot blight. Fungal pathogens like Phomopsis have been isolated from these bushes and in some cases these young bushes die. If you have a question about stem blights, it is best to submit a sample of MSU Plant & Pest Diagnostics. 

Senator Gary Peters Tours Blueberry Farm

On Friday, July 14th, Senator Gary Peters toured Crossroads Blueberry Farm and talked about his Spotted Wing Abatement Trust (SWAT) Act which would establish a fund managed by the USDA to strengthen efforts that mitigate the spread of the Spotted Wing Drosophila, helping to keep costs down for growers and prevent crops from being spoiled.  Peters is pushing for the bill to be included in the 2023 Farm Bill. 

Do You Use Quickbooks?

QuickBooks is one of the most widely used financial software packages for farm financial records. It is a powerful tool, but using it effectively for farm businesses can be confusing. MSU Extension is partnering with the University of Wisconsin and University of Nebraska to develop educational resources for using QuickBooks for farm records effectively and efficiently. It would be greatly appreciated if you would complete a short survey that will help us better understand what is desired for QuickBooks educational programming. Click the button below to take the survey!

Don't Guess, Test!

Growers have been submitting samples to the diagnostic clinic that range from stem blights to viral symptoms. Remember the Michigan Blueberry Commission has a program to subsidize any testing through MSU Plant & Pest Diagnostics. Click below to get more information about how to submit a sample.