The weather and pest forecasting dashboard is live! Check out values specific to your region at https://onvegetables.com/weather-dashboard/
Temperature – Day temperatures remain in the mid-teens to low 20s across Ontario and
many regions will see single digit night temperatures into the weekend. Environment Canada has issued a frost warning in northern and eastern Ontario. Cabbage maggot is at threshold in Wellington and Peterborough. Degree day data for each region is shown below.
Rainfall – There is no rain in the forecast for southern Ontario over the next week but eastern and northern Ontario have a small chance of showers towards the end of next week. Sudbury has now met it’s 10 year precipitation average and Huron county has surpassed it’s 10 year average. Precipitation data for each region is shown below.
Brassica Crops – Bacterial head rots in cabbage and broccoli are present in both southwestern and eastern Ontario. Downy mildew and Alternaria are widespread. Scout for aphids in the growing points of the plant and continue to monitor for late season flushes of thrips, especially in cabbage destined for storage.
Celery – Harvest continues. Multiple pathogens are present causing celery leaf curl, Cercospora leaf spot, Sclerotinia rot and bacterial rots. When scouting late in the season, avoid moving through the crop when the leaves are wet as pathogens can spread easily on clothes/equipment throughout the field. Continue to monitor for aphids, tarnished plant bugs, aster leaf hoppers, and leafminers.
Cucurbits – Phytophthora fruit rot of pumpkin caused by Phytophthora capsici has been found in several counties. Symptoms often appear where the fruit is in contact with soil. Because conditions have been conducive to the development of this disease, now is a good time to monitor for low levels of disease. Phytopthora can build in soils and if low populations are present, crops should be rotated away from cucurbits and solanaceous crops. Phytophthora produces motile zoospores which are attracted to plant root exudates and can swim through water films and spread throughout wet fields. Improving drainage can be helpful in managing this pathogen. It is important to clean equipment and sanitize footwear between infested fields. Harvest of infested fields should be scheduled after healthy fields have been harvested where possible.
Cucumber beetles are still active and can cause direct feeding damage to the rind of cucurbits, reducing marketability and potentially leading to infection.
Onions – Harvest is underway. No downy mildew outbreaks have been confirmed in Ontario.
NOTE: Data as of September 16th, 2020
Pest Degree Day Forecasting
|Pest||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: