Evaluating your canola stand early in the season provides an important snapshot of how well the crop has established and how closely it aligns with your seeding intentions.
Once emergence is underway, getting into the field to assess plant numbers and uniformity helps confirm whether plants are progressing as expected and can reveal early signs of stress or damage.
These early observations set the stage for interpreting stand counts and understanding why they matter for in-season decisions and yield potential.
Reaching Better Yields
Canola plant stands below 3 to 4 plants per square foot are unlikely to reach their full yield potential.
Your targeted plant stand is likely going to be a higher number than this, but it does vary depending on your field conditions.
Evaluating your plant stand helps you to determine whether you reached your plant population goals and if not whether next year there might be things to change at seeding to reach that target.
Knowing your plant stand can also help you make decisions around in-season threats. If your plant stands are critically low, you may consider lowering your thresholds for spraying insecticides and herbicides.
How to Conduct a Plant Count
Evaluating plant counts begins once the crop reaches the 2- to 4-leaf stage, when emergence is easier to assess. Checking multiple areas across the field helps capture variability caused by soil type, moisture, and residue. A representative average will give the most accurate picture of how the stand has established.
Using a Hoop
A hoop with an area of two square feet (49 cm diameter) provides a quick way to estimate plant density.
Place the hoop in several spots throughout the field and count the number of plants inside each placement. Dividing that count by two converts it to plants per square foot.
Using a Meter Stick
A meter stick can also be used by counting plants within one meter of row length. Converting this value requires multiplying the count by 100 and dividing by the row spacing in centimetres to find plants per square meter.
Dividing by 10 converts that value to plants per square foot. Volunteers should not be included in counts; check for blue seed coats or plants growing between seeded rows to distinguish them.
Comparing Plant Count to Seeding Rate
Once you’ve done a few plant counts and gotten an average for the field, you can compare this to your seeding rate.
What percent of plants actually emerged? The Canola Council has a great tool for this.
If your emergence rate was good but you’re still below your target plant population, that can indicate a need for a higher seeding rate next year.
Other reasons for being below your target plant population could be insect pressure, unfavourable field conditions or harsh weather events like frost.
Implications of Thin Stands
This spring has thrown some tough conditions at farmers. Dry starts and heavy frosts have had a lot of growers out in their fields checking their plant stands and possibly thinking about reseeding.
It’s always good to remember that canola plants are hardy and adapt to the conditions they’re put in. A thin stand will often create more side branches and can achieve close to its full yield potential. A late reseeded field may not be able to reach that mark.
Adapting In-Season Management
- Adjust pest and weed management: Thinner stands require more careful pest and weed monitoring.
- Update spray decisions: Make spray choices based on increased field vulnerability.
- Plan for extended maturity: Expect uneven and prolonged plant maturity with thinner stands.
Ideal Plant Counts
Every farmer and field has a different ideal plant count based on their field conditions. However, research shows that highest yields come from plant stands of 5 to 8 plants per square foot.
Achieving a close to ideal plant population is going to give your canola crop the best chance to reach its highest potential yield. Starting out with too many or too few plants immediately reduces a field’s yield potential and takes money out of your pocket.
Going out and counting is the only way to know where your field sits and if there’s anything you need to change this season or in future years to help maximize canola yields.
FAQ
Why is it important to evaluate your canola stand?
Evaluating your canola stand helps you make informed decisions about field management, assess if your seeding strategy was effective and plan improvements for upcoming seasons to reach full yield potential.
When should you conduct a plant count in canola fields?
You should evaluate your fields between the 2 to 4 leaf stage for the most accurate assessment of your canola stand.
What tools can be used to count plants in a canola field?
You can use either a plant count hoop with an area of two square feet or a meter stick to conduct plant counts.
What is the ideal plant stand for achieving the highest canola yields?
Research shows that the highest yields come from plant stands of 5 to 8 plants per square foot.
How do thin stands affect canola crop management?
Thinner stands make the field more susceptible to pest and weed pressure, may require changes in in season management and usually result in uneven, extended maturity.
What could cause a lower than target canola plant population even if emergence rates are good?
Reasons could include insect pressure, unfavourable field conditions or harsh weather events such as frost.
Why should you avoid counting volunteer canola in your plant counts?
Volunteer canola should not be included because it may not be growing in seed rows and does not accurately represent your intended seeding outcome.
