Strawberries

Strawberries: Crops are moving quickly now, and early June-bearing strawberries that were not row-covered are beginning to bloom. There is bloom on row-covered fields and green fruit and bloom in day-neutral strawberries. Insect activity has increased this week. Watch for aphids, tarnished plant bug, clipper weevil, cyclamen mite, and two spotted spider mite.

• Aphids: strawberry aphids can be found in June-bearing strawberries. Following our strawberry virus survey in 2023, we found aphid management is working to control viruses and improve longevity of strawberry fields, but maintaining regular aphid control is still important. Dimethoate (Cygon/Lagon/Diamante), Exirel, Beleaf, Sivanto Prime, Cormoran, or Assail/Aceta can be applied before bloom, or Sivanto Prime or Beleaf during bloom. Assail and Beleaf will also control TPB. Do not use Admire at this timing; Admire cannot be used pre-bloom or during bloom. Apply post-bloom only.
• Mites: Cyclamen mites have been found in June-bearing fields. If cyclamen mites are identified apply Agri-mek at 225 mL/ha in a high-volume spray (minimum 375 mL/ha), with a non-ionic surfactant at 0.1-0.5%, where permitted. It is very important to get thorough coverage- slow down and use a high volume. Agri-mek can only be used twice a year.
• Timing can be challenging: Make sure to keep a 5 day gap between Agri-mek or oil applications and chlorothalonil (Bravo or Echo) or captan applications. Do not apply sinbar after applying Agri-mek. Wait 5-7 days after Agri-mek before applying sinbar.
• Magister has recently been registered for two-spotted spider mite (TSSM) control on strawberries, and has some activity on cyclamen mite as well.
• Clipper weevil: clipper weevils and clipped buds are beginning to be found in June-bearing strawberries. Pay close attention to your older fields, and monitor field edges for clipped buds. Group 3s or Cormoran can be used for clipper weevil control before bloom if needed.  Border sprays may be sufficient at minimizing clipper weevil damage.

• Tarnished plant bug: nymphs are beginning to be found. Beleaf applied at the high rate during bloom will suppress TPB and control aphids.

• Disease management: As we move into bloom apply broad spectrum fungicides (group M) as much as possible for disease control.  Do not rely on group 11 products for anthracnose control. Disease prediction models are available this year to help with controlling anthracnose and botrytis. See below for more details.  
• Our Suggestions for Anthracnose Management in Strawberries, 2024, have been updated for the season. See the onfruit.ca blog for these guidelines on managing this challenging disease.  

Strawberry Disease Decision Support System

Anthracnose and botrytis are the major fruit diseases in Ontario strawberries. By integrating a disease prediction model into management, growers can use fungicides more effectively to protect their crops through the season. A map indicating anthracnose fruit rot and botrytis risk is available for growers to use this season to help assess the risk of disease epidemics from bloom to harvest.

The Strawberry Diseases Decision Support System can be found on the ONfruit blog under the ‘Berries’ tab, or you can bookmark this page:  2024 Strawberry Disease Decision Support System. The Strawberry Diseases Decision Support System includes a map indicating fruit infection risk across the province and a graph tracking risk through the season.

Blueberries

Blueberries are in bloom in southern Ontario.

• Spongy moth: Widespread spongy moth defoliation is not likely in 2024, but watch for them in new blueberry fields. Newly hatched caterpillars are small, dark, and hairy, and feed on young blueberry fields. Young blueberry fields can tolerate less damage than established fields.  
• Cranberry and cherry fruitworm begin to fly at bloom. Use pheromone traps to time insecticide applications or plan to apply insecticides at petal fall.

Raspberries:

Raspberries are leafing out and we are starting to see fruit buds. Begin to monitor for raspberry fruitworm and strawberry clipper weevil once fruit buds are present using a tapping tray or dish.

Protect growing primocanes and developing laterals with fungicides before and during bloom. Tanos is registered for cane diseases, but Pristine and Switch also do a great job on cane diseases when they are used to control Botrytis grey mould. Good coverage is important.

• Crown borer: Diazinon is no longer registered on raspberries. If crown borer control is needed plan to apply Altacor in late August or early September.

IPM workshops:

• Strawberry & Raspberry IPM Workshop: Scout training workshop (free)

May 14, 9:00 am- 1:00 pm. 1283 Blueline rd. Simcoe, On. Click here to register.