Winter canola isn’t actually that new of a crop to Ontario — there were certainly some acres produced in the 80s and 90s — but there’s been a resurgence in the last five years with increased availability of a new variety.
Meghan Moran, OMAFRA canola and dry edible bean specialist, joins Bernard Tobin in a winter canola field to talk about agronomic decisions and more in this Canola School episode.
In terms of rotation, winter canola typically follows winter wheat in Ontario, because of the time of year it needs to be planted. Moran says that in theory, winter canola could also follow fresh peas, but there are some herbicide restriction that make that difficult.
The optimum planting date has been trialled as late as September 20, but Moran says she prefers to see winter canola go in the ground earlier in September, depending on the region.
In the video, Moran and Tobin are in a field that was planted September 5, story continues below.
The optimal plant population for winter canola is a bit different from the spring canola grown in the west, says Moran. “We know that canola can yield strongly from five to 20 plants per square foot, but we’re really worried about overwintering in winter canola. So if we give plants space to grow a little bigger in the fall, they set their crowns nice and close to the soil surface.” Moran aims for five to seven plants, and no more.
One of the drivers of success for crop establishment in the fall is tillage, especially following winter wheat. “Residue really leads to big problems with slugs, and slugs are really plentiful in the fall,” says Moran. Thirty to forty pounds of actual nitrogen, and ten to 20 pounds of sulphur are necessary, to get the crop to the six-leaf stage with a good root size, about the size of a pencil, by the end of fall — winter-kill is the biggest risk.
In the spring, there’s ideally a gradual, consistent increase in temperature and Moran says that late-spring frost can be a problem, aborting flowers or buds that are present.
The biggest disease risk for winter canola is sclerotinia, which can be managed with a fungicide application at 20 to 50 per cent blooms. Moran says that they’re monitoring for clubroot, and it could be a problem similar to in spring canola. As for insect pests, cabbage seedpod weevil is the main concern.
Moran says that typically winter canola is harvested in early July, and that a reasonable yield goal is around 70 bushels or 3500 pounds per acre, and to fertilize with that yield goal in mind.
There’s also the option to double-crop soybeans in the southern region, depending on rainfall. Moran adds that there’s a lot of opportunity to increase acres of winter canola, lengthen crop rotations, and diversify those canola acres to avoid risks of spring canola pests.