Whether it’s chickpeas, fabas, lentils, or peas, proper nodulation is key to ensuring a healthy, nitrogen-fixing pulse crop, and it all starts early in the season. Achieving that happens pre-seeding, with proper inoculation. But what happens if nodules don't form?
In this episode of RealAgriculture's Pulse School, Shane Strydhorst of Pulse Canada and Alberta Pulse Growers joins RealAgriculture’s Amber Bell to dig into why nodulation matters, how to scout for it, and what to do when things go wrong.
“Nodulation is the magic that makes pulses great,” says Strydhorst. Plants that lack nodules early on — especially by the two- to four-leaf stage — may not be fixing their own nitrogen. That can mean a pale colour, weak growth, and ultimately lower yield, says Strydhorst.
There are a few common causes of nodulation failure, including forgetting to apply inoculant, seed treatment incompatibility, or leaving treated seed too long before planting. Strydhorst stresses the importance of checking your labels and application process to avoid costly mistakes. He says that some farmers assume inoculant is part of the seed treatment when it isn't and that can really set the crop back.
If a nodulation issue is caught early, a rescue nitrogen application may help, but you’ll need to apply a significant amount to support the crop, Strydhorst says. Pest pressure, such as from pea leaf weevil, is another risk to keep on the radar, as they feed on nodules underground.
For growers looking to stay ahead of potential nodulation issues, early scouting and proactive management are key. Taking the time to dig up plants, inspect nodules, and confirm healthy nitrogen fixation can pay dividends in yield and crop performance, he says.
