Across the Canadian Prairies, soil moisture reserves are much lower than normal, thanks to a drier autumn and less snowfall than usual this past winter.
You may be tempted to seed deeper to find moisture, especially if you’re seeding into ground that’s extremely dry.
But as agronomists like Justine Cornelsen will tell you, if you’re betting on this high risk/reward strategy to pay off with a bumper crop this season, the odds are stacked against you.
Risks of Seeding Too Deep in Dry Soils
Cornelsen, who’s an Agronomy Specialist with the Canola Council of Canada, recommends a seeding depth of ½” to 1″. Any deeper than that, and it’s likely the seed will struggle to germinate and make it out of the ground.
“People do push it sometimes, but you need everything in your favour to get those seeds up,” Cornelsen says. “Otherwise, your risk is going to be much higher for losing plants.”
Cornelsen explains that because canola seeds are so small, they have a limited amount of energy available to successfully germinate and emerge. When seeds are too deep in the soil, that energy is used up before the seedling can make it to the surface.
Seeding Depth Recommendations for BrettYoung Canola
Rene Mabon, Agronomic Services Manager for BrettYoung, also recommends a ½” to 1″ seeding depth for BrettYoung’s TruFlex®, Roundup Ready® and Clearfield® canola varieties, since that’s shown to lead to the most reliable stand establishment.
Mabon says seeding deeper than that not only risks creating issues with seedling survival, but it can also make the young plant more prone to seedling diseases, like damping off.
“Seed too deep, and you will lose seedlings. Seed shallow (in the dust), and you don’t get enough moisture to start germination, so you are in the same place,” says Mabon. “I’m a risk-taker, so I would tend toward seeding a bit deeper to find moisture this spring, and I’d up my seeding rate a bit to compensate for the likely losses.”
Weather, Wind, and Planting Timing
As Cornelsen and Mabon both point out, there’s also some risk if you don’t plant deep enough. When moisture reserves are low, as they are now, and the soil is dry and dusty, strong winds can blow soil and exposed seeds away.
That’s why Cornelsen recommends keeping an eye on the weather and holding off on seeding if the forecast is for high winds, like the 80 km/hr winds we saw in late March this year.
Canola does require some soil moisture to germinate, so she also recommends getting your canola fields planted just before a rain event this spring if your fields are dry, an option producers have this year with the open spring.
Importance of Seed-to-Soil Contact
Cornelsen notes canola needs good seed-to-soil contact so it can access soil moisture. Given the current situation, with low soil moisture reserves, she recommends avoiding spring tillage and trying to direct-seed if you can.
“It doesn’t take a lot of moisture, but there has to be some for the seeds to start germinating. That’s why seed-to-soil contact is so important,” she says, adding that you can play around with packing pressure while planting this year as a way to increase seed-to-soil contact.
“The soil might be really dry, but if you can pack the seed firmly so it’s surrounded by whatever available moisture that’s there, that’s going to increase its odds of going up this spring.”
Soil Temperature Targets for Canola Emergence
Soil temperature will be another important consideration for you this spring. According to the Canola Council, a good starting point for seeding canola is when the three-day average in the seed zone is 4 to 5°C, around the temperature when biological activity usually begins.
- Minimum soil temperature: Mabon recommends having a soil temperature of at least 5°C when planting canola.
- Faster emergence range: He says 7 to 10°C is better for faster emergence, though yield benefits still support seeding early.
- Yield benefits of early seeding: Earlier spring-sown crops often flower before the hot conditions in late July, supporting higher yields.
- Risks of ultra-early seeding: Many early seeded canola crops become more vulnerable to spring frosts and extreme flea beetle feeding.
- Definition of early seeding: In this context, early to mid-May is classified as early seeding. April is considered very early seeding.
Get Support for Your Seeding Plan
If you would like more information or support with determining the proper seeding depth for your farm this spring, contact your BrettYoung Regional Account Manager.
FAQ
How are drier Prairie springs affecting canola seeding?
Soil moisture reserves are much lower than normal because of a drier autumn and less snowfall than usual, which is leading many growers to reassess seeding depth and timing so canola can still emerge well.
What seeding depth is recommended for canola in dry soils?
Justine Cornelsen and Rene Mabon both recommend a seeding depth of one half inch to one inch for canola, including BrettYoung TruFlex, Roundup Ready and Clearfield varieties, since this range has shown to lead to the most reliable stand establishment.
What are the risks of seeding canola too deep or shallow?
If canola is seeded deeper than one inch, the small seeds can run out of energy before emerging and are more prone to seedling diseases like damping off. If seed is placed too shallow in dry, dusty soil, there may not be enough moisture to start germination, which can leave you with poor emergence as well.
How should weather and wind guide spring canola seeding?
When moisture reserves are low and soil is dry and dusty, strong winds can blow soil and exposed seeds away if you seed too shallow. Cornelsen recommends watching the forecast, avoiding seeding ahead of high winds like the 80 kilometre per hour winds seen in late March, and trying to seed just before a rain event if fields are dry.
Why is seed-to-soil contact vital in dry canola fields?
Canola needs good seed to soil contact so it can access the limited soil moisture available. Cornelsen suggests avoiding spring tillage and direct seeding if possible, and adjusting packing pressure at planting so seeds are packed firmly and surrounded by whatever moisture is in the soil.
What soil temps and timing are best for seeding canola?
The Canola Council suggests to start seeding when the three day average soil temperature in the seed zone is 4 to 5°C, and Mabon recommends at least 5°C, with 7 to 10°C providing faster emergence. Seeding earlier in spring can improve yield by helping the flowering period avoid hot conditions in late July, but very early seeding such as at the beginning of April can increase the risk of spring frosts and extreme flea beetle feeding, so early to mid May is considered early seeding.
Where can I get support for setting canola seeding depth?
If you would like more information or support in determining the proper seeding depth for your farm, you can contact your BrettYoung Regional Account Manager.
