Question: When is the ‘Right’ Time to Seed Canola?
Answer (submitted by Anastasia Kubinec, MAFRI Oilseed Crop Specialist):
The ‘right’ date to seed canola will change every year in Manitoba. Earlier works in some years, but not all.
To set your canola crop up for a good start in all years, fields should be monitored to assess when machinery can successfully get across and when soil temperatures are warm for quick seedling establishment (average 5C or higher). Also, planning seeding dates to avoid the last spring frost, or have canola seedlings at a stage where they can handle a frost event better (3 to 4 leaf canola is less susceptible than at the cotyledon stage).
Looking at the Manitoba Agricultural Services Corporation (www.masc.mb.ca) data on canola seeding date and yield (2000-12), most of May looks pretty good as a seeding date. For the first three weeks (May 1-22), canola yields regionally are above 100%. In the fourth week of May (May 23-31), yields are around 95% or higher (see Table 1: Manitoba Canola Yields by Seeding Date (2000-2012)).
Looking at the acres seeded, it shows Manitoba farmers typically do seed the majority of the canola crop in May (64 – 89% depending on region). Figure 1: Manitoba Canola Acres Seeded by Week (2000-2012). So for the most part, Manitoba farmers have the timelines for the ‘best’ seeding dates figured out pretty well (if the weather co-operates). But please remember the other factors that will boost establishment and yields – not seeding too fast, not putting seeds too deep (or shallow) and proper fertilizer placement and amounts. Even though the entire month of May looks good for seeding canola, we usually only get one chance to do it right!