OMAFRA Report: Winter canola plant survival

A weekly report prepared by the staff of the Ministry of Agriculture, Food and Rural Affairs (OMAFRA).  If you require further information, regarding this report, call the Elora Resource Centre at 519-846-0941.  Office hours: 8:30am to 4:30pm.For technical information call the Agricultural Information Contact Centre at 1-877-424-1300 or visit the OMAFRA website:

April 2, 2021


When spring arrives, winter canola growers will have to scout their fields and answer 3 questions before applying fertilizer:

1. Is the canola alive?

2. Does it have strong yield potential?

3. What is the population of healthy plants?

Scouting typically begins towards the end of March when plants start to green up. Assessments should be made after the risk of further losses from cold conditions, or fluctuating temperatures, has passed. Information from the canola breeding program at Kansas State University suggests that freezing tolerance is lost when temperatures are above 15°C for an extended period. Assessments could be made prior to temperatures reaching 15°C and above; however, if temperatures drop below that you may need to scout again.

In March, if you “scout” from your truck you might jump to the conclusion that everything looks dead if all the leaves have fallen off or turned brown. Some fields do not retain all the green leaves they put on in fall, especially if there was an abundance of vegetative growth. It has been observed that plants with fewer leaves (but adequate root growth) in the fall tend to retain those leaves through winter, whereas plants with many large leaves in the fall tend to lose those leaves through winter.

Please see website for entire article with photos –

Written by Meghan Moran, Canola and Edible Bean Specialist, OMAFRA and published on March 3, 2021.


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