AIRDRIE, Alta. — A cool, damp spring and a wet summer have some farmers watching the weather and whispering the ‘f’word.
Frost is on the minds of many and for canola growers in the Calgary region, it is a concern because the first freeze could come as soon as Sept. 11.
Early frost can present a problem in this area because of the high elevation farming at 3,000 to 4,200 feet, said Herman VanGenderen, who represents Pioneer Hi-bred seed sales.
The rain in late May delayed seeding. Consequently crops are not maturing at a normal rate.
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“The crop is ahead of last year but behind normal,” he said.
“The biggest problem I see is there are a lot of fields with a lot of hail damage. There hasn’t been a complete wipe-out storm, but there have been about 10 clouds that rolled through,” he said during a Pioneer Hi-Bred canola crop tour Aug. 17 near Airdrie.
Maturity is the biggest concern this year.
“If those fields have avoided hail, the crops are good but they are not great because the frost damage could happen.”
Disease is also present.
“The next two weeks will tell us how much sclerotinia was actually in the area,” said VanGenderen.
Farmers with a lot of canola acres may be anxious to start swathing
soon to get ahead of sclerotinia and frost, said Dan Orchard, of the Canola Council of Canada.
Canola can stand 0 C to -2 C for an hour or two but a longer freeze from -3 C to -5 C can be deadly.
“Watch the weather and knock down the more advanced crops,” he said. “You need two or three days of decent drying weather before a frost to get it out of the woods as far as locking in the green seeds,” he said.
Extreme temperatures that are either too hot at more than 30 C and/ or cold in the fall can lead to rapid drying of plant cells and can set the green seeds.
The canola council advises the optimum stage to swath is when about 60 percent seed colour change has occurred on the main stem.
The longer swathing is delayed the better the yield and quality. Seeds are bigger, there are fewer green seeds and oil content is higher. Swathing could start when about 20-30 percent of seed colour has occurred.
That colour change may only be the size of a freckle to start, said Orchard.
Plant or pod colour varies among varieties and growing conditions.
Some varieties can appear ripe on the outside before the seeds are mature.
Swathing during the cool of evening and early morning allows plants in the swath to dry down at a slower rate and reduces the chance of downgrading due to green seed.
Protection from frost damage results mainly from dry down of seed in the swath, so sufficient time between swathing and the frost event is needed.
