A mediocre approach won’t cut it when growing canola

When you’re spending upwards of $400 an acre to grow this crop, yield-robbing mistakes are painful

With pulses slamming into India’s tariff wall, it’s not surprising many producers are thinking about more canola this year.

However, even experienced canola growers can trip up with the small-seed crop.

The biggest obstacles are a high failure to make a plant, its slowness to establish, and seed cost, said Greg Sekulic, a Canola Council of Canada agronomist in the Peace.

Canola Council of Canada agronomist Greg Sekulic.
photo: Supplied

“As aggressive a crop as canola can be once it’s established, it’s actually a frail little plant to get started,” said Sekulic.

“The greatest contributors towards success growing canola include shallow, uniform seeding while paying attention to seed density, plant spacing, and seeding speed.”

Still, strong canola prices and high demand make the crop almost irresistible, said crop specialist Harry Brook of Alberta Agriculture and Forestry.

“I expect to see a lot of the countryside yellow,” said Brook. “Our alternatives — which would have been peas and lentils — are not doing so well this year because of India’s tariff trade barriers.”

But Brook isn’t entirely comfortable with canola as an alternative due to its high expense and seed failure rate (because the seeds are small and don’t have a tremendous amount of energy reserves).

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“The biggest conundrum with canola seed is — even at the best of times — only 50 per cent of the seeds will make plants and that’s despite germinations in the 90 per cent range,” he said. “You plant seeds which should result in 16 plants per square foot, but you only get seven or eight.”

Couple that with the cost (from seeding to harvesting) that can reach $400 an acre and you’re taking on a lot of risk, he added.

“That’s a lot of money hanging out there just for the chance to break even with an average-yielding crop.”

On the other hand, when all goes well, virtually nothing can be as profitable.

“Looking at the economics of almost all the crops, canola still comes out on top,” said Brook. “It’s frustrating from that point of view. We still keep looking for something else that will give us better returns with lower costs, and it’s really hard to find.”

Keys to success

Producers’ first stop before planting canola should be the Canola Calculator on the Canola Council of Canada website, said Sekulic. This tool offers plant density and seeding rate suggestions based on a number of factors specific to growing conditions.

The odds of a good canola stand are greatly increased by planting seed no more than an inch — and less than an inch if possible — into the soil. This necessitates a moist, firm seedbed, said Sekulic.

“The best way we’re going to achieve that is through zero till so you leave as much moisture as close to the surface as possible. It’s going to give us the best start, absolutely.”

Planting below that inch is risky but extremely easy to do, especially when using poorly calibrated seeding equipment.

“I’ve seen a number of fields planted in excess of two, maybe even three inches below the soil, which isn’t that difficult to do if a person’s not checking extremely regularly,” he said.

“Canola will emerge to a lesser extent at that depth but we see sharp declines in plant stand and yield as we increase our seed depth by an unnecessary half-inch every step,” said Sekulic. Unfortunately, this no-more-than-an-inch rule does not change when planting larger canola seeds.

“While it would be plausible to expect larger seeds to have more vigour, the survivability as you start increasing that depth down past an inch really stays pretty constant.”

Lay off the gas

The ideal plant stand is six to 10 plants per square foot. This gives the greatest chance of reaching a high yield as it offers enough of a buffer to deal with losses from frost and insect damage.

“As that curve starts to move down to fewer and fewer plants per square foot — say around five plants per square foot or so — we start to limit ourselves to around 80 per cent of yield potential,” said Sekulic. “Obviously that increases with a non-uniform stand as well, so if there are clumping or germination issues that affects yield as well.”

Having the right number of plants can be even more important than a uniform stand, but ideally you want both, he added.

“You can have a pretty scrappy-looking stand but if you get in excess of eight plants per square foot you will achieve your natural yield potential easily. However, we’ve seen in research that if your stand is non-uniform we give up about 20 per cent yield. So you really need uniformity to be the equal partner to absolute plant numbers.”

So how do you achieve that degree of uniformity?

In addition to shallow planting, a slow seeding speed is essential.

“While I don’t really have the perfect speed for seeding, I can pretty much say a little bit slower is going to be a little bit better,” said Sekulic. “There are a few new seed designs (in newer varieties) that can handle increased speed but it’s rare that I’ve seen an operation that can plant uniformly, evenly and properly in excess of five miles an hour.”

It’s tough to be above average

So if you slow down and plant no more than an inch deep, will you break canola’s infamous 50 per cent plant loss barrier?

“Some producers who have paid a lot of attention to seeding speed and depth uniformity are averaging in the high 70s and 80s,” said Sekulic. “It’s definitely very possible.”

It’s also pretty rare.

“At the research farms we analyze the number of seeds per square foot and count the plants afterwards. Fifty per cent is a pretty common number.”

What you definitely don’t want is seeds placed side by side.

“Even in the greenhouse, when we take 10 seeds and put them in one hole in pretty light soil media, we’ll see maybe 30 per cent emergence — maybe two to four of those seeds were ready,” said Sekulic. “Otherwise, we’ll take that same seed lot and spread them out about an inch apart and we’ll see them all grow.

“It seems when seeds are clumped together they seem to inhibit each other’s germination. That’s something that’s pretty common, both in field and laboratory studies.”

But seed breeders are making gains.

“We have literature going back into the ’80s and ’90s talking about ideal plant stands,” said Sekulic. “They were doing work between 1-1/2 to 3-1/2 grams per 1,000 seed weight and they said their emergence topped out at 3-1/2 grams per 1,000 or so.

“Nowadays, with modern hybrids and the varieties we’re using, we’re starting at that 3-1/2 grams per 1,000 and extending up into seven grams per 1,000.

“While it’s not new that there’s a variable size to the seed, it’s certainly new that 1,000 seed weights have got that large.”

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