Top Crop Manager

News Corn Seeding/Planting
Ontario producers swap corn hybrids to deal with shorter season

Wet weather has stalled provincial seeding progress at 15 per cent, and now growers are starting to switch corn hybrids to lower maturities to make the most of a shorter season.


Only 15 per cent of corn has been planted across Ontario because late wet weather has saturated soils and left field conditions unfit for planting,¬†according to the latest crop report from Ontario’s Ministry of Agriculture, Food and Rural Affairs (OMAFRA).

Corn planting progress mirrored the weather conditions, with drier areas seeing seeding progress and wetter areas seeing a delay in progress. Lighter-textured ground and areas that have seen a few days of favourable weather, such as parts of Grey, Bruce, and Huron counties, are between 50 to 80 per cent planted for their corn crop.

However, other areas such as southwestern Ontario, that have experienced consistent wet weather or have heavy soils remain almost completely unplanted. For southwestern Ontario, the delayed seeding in spring follows wet conditions in fall that resulted in high levels of mycotoxins, specifically deoxynivalenol (DON), in corn and only adds to the bad news for growers in that region.

As a result of delayed seeding, growers across the province are starting to switch hybrids to lower maturities. The field crop team at OMAFRA explain that historically it has been more profitable to plant lower-maturity hybrids than to run the risk of the crop not achieving full maturity before the average first frost. If switching, hybrid differences must be 200 Crop Heat Units (CHUs) or more to make a real difference in the field. Table 1-8 of the Agronomy Guide for Field Crops shows the recommended dates to switch from full-season hybrids across various heat unit zones.

Corn is particularly sensitive to being “mudded in.” The OMAFRA field crop team explain it is better to plant appropriate maturity corn later in fitter ground, than to try and plant corn in muddy conditions. Instead, producers can consider planting soybeans in tougher conditions first to give corn fields a bit more time to reach better conditions. Or, producers are encouraged to consider cutting hay instead because forages lose quality faster than corn loses yield potential.

The availability of seed for those switching hybrids is not a concern, but there is some concern that lower heat unit zones will have limited options for non-neonicotinoid-treated seed in lower maturity groups. The OMAFRA field crop team shares their resource Switching Hybrids and Class 12 Pesticides as a resource for growers looking for alternative options.