The Vegetable Crop Report is back for another season! We hope that your field season is off to a good start despite the cool wet weather we have had in many regions over the past month.
Temperature: Temperatures are on the rise next week with a forecast of high teens and even low to mid-twenties in some areas. *UPDATE (12/05/2022): The 10-year average GDD calculation has changed to better reflect the current weather trends. Durham, Peterborough, and Kemptville are meeting their 10 year GDD averages however all other counties are lagging behind.
Rainfall: Little rain is forecasted over the next week with full sun expected in most counties over the next 7 days. Most counties are lagging behind their 10-year precipitation averages for March and April with the exception of Huron, Kemptville and Sudbury which surpassed them in March.
Brassica Crops – A significant portion of transplanting has been postponed to this week as many regions have seen some very cool nights. Some fields that were planted are showing frost damage with the outer most leaves turning purple or yellow. While it has not been warm enough for cabbage maggot fly to reach its first-generation growing degree threshold in any county, seedcorn maggotfly is active in most regions. If you were unable to attend the Brassica Crops IPM scouting workshop, a recorded version here:
Garlic – The amount of winterkill over the 2021-2022 winter has been high. Many fields were too wet to be planted in September and October and later plantings did not have much time to produce good root establishment before the ground froze. Many fields that were planted were saturated which may have resulted in more frost heaving and injury. Areas experiencing hard frosts with night-time temperatures below -4°C are showing tip burn on the older leaves. Overall, plants are at the 4-6 leaf stage in more southern regions. Now is the time to set up leek moth traps as adult moths emerge from overwintering sites and are looking for a place to lay eggs once the night temperatures remain above 9.5°C for two consecutive nights. Some areas with microclimates may have already had some adult leek moth activity as seen from this picture taken in Guelph, ON. If wilted plants are seen while scouting, dig up the plant and inspect the roots for wireworms or seedcorn maggot larvae. If your garlic already shows leaf damage due to an insect, please send photos to firstname.lastname@example.org.
Onions – The cool, wet weather has slowed germination and made transplants slow to establish in fields that have been planted. Once the flag leaf has emerged, count out 25 plants per row and put a stake at each end. Record the number of plants over the next few weeks and monitor for damage due to maggot flies, damping-off or cold weather. Register now for the Onion IPM Scouting workshop on Thursday, May 12th. Onion insect and pathogen scouting will be the focus of the in-person and virtual workshop.
More Upcoming Workshops:
Carrot – Register for the upcoming Carrot IPM workshop on May 12th.
Cucurbits – Register for the upcoming Cucurbit IPM workshop on May 18th.
Sweet Corn – Register for the upcoming Sweet Corn, Peas and Beans IPM Workshop on May 11th
Pest Degree Day Forecasting
*NOTE: Data as of May 4, 2022
|County||Carrot Rust Fly||Onion Maggot||Carrot Weevil||Aster Leafhopper||Tarnished Plant Bug||Cabbage Maggot||Seedcorn Maggot||European Corn Borer|
|THRESHOLD||329-395, 1399-1711||210-700, 1025-1515||138-156, 455+||128+||40+||314-398, 847-960, 1446-1604||200-350, 600-750, 1000-1150||See legend below|
*- Bivoltine region for ECB. First Peak Catch: 300-350 DD, Second Peak Catch 1050-1100 DD
**- Overlap region for ECB. First Peak Catch: 300-350 DD Second Peak Catch 650-700 DD, Third Peak Catch 1050-1100 DD
***-Univoltine region for ECB. Peak Catch 650-700 DD
Use these thresholds as a guide, always confirm insect activity with actual field scouting and trap counts.
Select a region below for the latest weather, crop and pest degree day information: