Frost quiz – April 26, 2016

These seedlings suffered severe frost damage, but it looks like one late-emerging survivor is poking through. A couple of these per square foot could be enough to produce a good crop. Credit: Deanna McLennan
These seedlings suffered severe frost damage. Credit: Deanna McLennan

1. If the average date of the last -3°C frost in your area is May 1, what is the probability that a killing frost will occur on or after that date?
2. If you are OK with subjecting canola to a 50% probability of a -3°C frost on May 1 (as described in question 1) and if it takes 10 days for canola to emerge, what would be a reasonable time to start seeding canola in your area?
3. If a -3°C frost hits a canola crop, what situation is more likely to result in higher levels of damage?