By: Wendy McDonald – MPSG Production Agronomist – West
On April 30, 2026 it was a bright and sunny day near Inglis. At 2 inch depth, on a high spot of a field of wheat stubble, the soil temperature showed 7.8°C.
Let’s take a look at the current pea situation.
The snowbanks in the bush line need a few days to melt and the low spots are squishy, so it is best to wait before starting seeding.
On April 30, 2026, near Salt Lake the soil surface had some cracks and the late afternoon soil temperature registered above 9°C.
Would it have been okay to start seeding peas with these conditions?
Looking ahead, the forecast seemed to be calling for “much colder than normal” conditions.
Not far away, east of Rivers I did spot a farmer out seeding, as the sunshine warmed his mellow and black seed bed.
On May 4, 2026 it started out quite chilly and farmers were asking if they should start seeding their faba beans that morning? Or should they be concerned that if the inoculant, after it was banded into the soil, could “die off” due to the potential for soil temperatures to drop later in the week? In fact, the overnight forecasted air temperature was supposed to go below zero for the next couple of nights and maybe even as low as -7°C.
BASF Ag Solutions Centre let us know that as long as the soil temperature stays above 0°C, there should be no harm to the inocculant rhizobia applied. If the soil temperature drops below 0°C, then we may see reduced viability of the applied inoculant.
Mark Zatylny from Saskatchewan Pulse Growers mentioned that the granular form of inoculant might fair a little better in colder soils than liquid or peat types, because the sphere of the granule acts like a little micro climate in the soil.
Conditions vary from field to field depending on the amount and type of residue cover, if it is going to be cloudy or sunny during the days, and for how long the below zero temperatures will persist. Sunny days, even with cool temperatures, can still warm the soil. Some soils can retain heat well and take a while to cool down.
How would it have turned out?
Around Erickson, how would the faba beans and inoculant fared if they had been seeded on the morning of May 4 when the 2″ soil temperature was +2°C? Unfortunately the soil temperature would have dropped to around 0°C for the next 3 nights. (Conditions reported at the Minitonas and Ashville weather stations were similar.)
Although the soil temperature did rise to +7 to 8°C during the day as time went on, 6 nights after May 4 the over night soil temperature dipped back closer to +1°C. That may have come very close to being unhospitable conditions for live rhizobia inoculant in the soil. Research does claim that if inoculant gets into micro-pockets of water within the soil that don’t completely freeze, even with sub zero soil temperature, it can survive.
Another question asked was “I have this pallet of dry inoculant sitting in my unheated shed, should I be concerned?” Storing inoculant at optimal conditions will ensure the rhizobia (living, breathing bacteria) you paid for will work the best it can once you get it in the soil.
According to many inoculant manufacturer’s websites:
1. Keep it between 4° C and 25° C
Outside of this range they can start to die off. This can happen in a very short period, such as inside the cabin of a truck, so don’t expose inoculants to temperature extremes for even a short period of time
2. Do not freeze
The bacteria in modern inoculants are designed to be very hearty and durable but allowing inoculants to freeze can kill them.
3. Keep out of direct sunlight
Exposing your inoculant to sunlight will have a negative effect as the UV rays kill off some of the active bacteria.
4. Keep away from wind
5. Store separate from pesticides and herbicides
Rhizobia are just like any other living thing that requires oxygen; if we put them in an airtight container, they would eventually die from lack of oxygen. The membrane of the storage bags is permeable to certain gasses, and noxious chemicals can enter the bags. So, it’s important to store your inoculants in an environment out of the wind and free from any pesticide and herbicide fumes that could, over time, reduce the performance of your inoculant.
*these 5 tips are from the XiteBio® website
So yes moving the pallet of dry inoculant to a heated shop (but not too hot) or “tucking the pallet in for the night” by covering with a blanket to trap some warmer air and insolate could be beneficial.