By Connor Lynch
GUELPH — There’s a saying out in farm country: If you can’t farm, grow soybeans.
It’s not quite right, said OMAFRA soybean expert Horst Bohner. But it’s not quite wrong either.
“They’re grown on every continent except Antarctica, because they’re relatively easy to grow and grow relatively well,” he said. Soybeans are notorious for being stubborn crops: Hard to kill but hard to get bigger yields out of as well.
They’ll adapt to plenty. Plant a small population and they’ll branch out to take advantage of the space. Plant a dense population and they won’t. They fix their own nitrogen and massively over-flower. As many as 80 per cent of a soybean plant’s flowers never produce a seed by the end of a season, he said. But if conditions improve through the season, those flowers will make a seed.
When it comes to planting dates, they’re a lot less picky than corn is. Bohner said he’s seen years where soybeans planted on April 20 and on June 20, turned out similar yields. “That’s absolutely amazing.” That’s not typical, but even late-planted soybeans don’t tend to lag behind all that much.
But the self-reliance of soybeans makes them hard to manipulate. “It’s pretty easy to grow a 40 bushel per acre soybean. It’s very difficult to grow an 80 bu/ac crop.” In 11 of the past 13 years, Ontario soybean yields have held in the 40.2 bushel per acre to 46.3 bu/ac range.
The fact that they branch means population density mostly matters for disease. No difference in disease problems, and a 90,000 population crop and a 300,000 will yield about the same, he said.
So what’s the secret to better yields? Making sure plants grow and keep pods. The record-breakers getting 100 bu/ac soybeans have figured out how: Pour money into those plants, way more than is cost-effective, said Bohner. What conventional producers need is a way to get soybeans to keep their pods that doesn’t involve remortgaging the farm equipment. Once researchers have a better handle on that, yields can start to climb for regular farmers.