The Horrid F Word: Frost
Erika DeBrouwer, Tree Fruit Specialist, OMAFRA
With the recent weather taking a turn (cold to hot to cool) and with how fast apples have progressed, 2023 has really been testing growers. This week temperatures are dropping, making it important to review critical temperatures, frost mitigation strategies and frost damage assessments.
Critical Temperatures
Apples | Silver Tip | Green Tip | ½ inch Green | Tight Cluster | First Pink | Full Pink | First Bloom | Full Bloom | Post Bloom |
Old temp | -8.9 | -8.9 | -5.6 | -2.8 | -2.8 | -2.2 | -2.2 | -1.7 | -1.7 |
10% kill | -9.4 | -7.8 | -5.0 | -2.8 | -2.2 | -2.2 | -2.2 | -2.2 | -2.2 |
90% kill | -16.7 | -12.2 | -9.4 | -6.1 | -4.4 | -3.9 | -3.9 | -3.9 | -3.9 |
Frost Mitigation and Assessment Resources
- Weather risks: strategies to mitigate the risk of frost
- Frost mitigation strategies article
- Frost bud assessments
Erika DeBrouwer
Tree Fruit Specialist, OMAFRA