Though corn crops have been having a tough start to the growing season, it doesn’t mean their full potential can’t be reached. With most of the Prairies at 10% to 15% below the average heat units for June, the corn sure has not been thriving like it has in previous years. Cooler temperatures and saturated fields don’t make for great conditions for the heat loving crop but with the July heat, things are looking up.
Did you start off right? #
Hybrid selection for any type of corn grown in the prairies should be done based on maturity and required corn heat units (CHU). Typically, silage corn hybrids can be slightly later in maturity than grain corn, which is around 100 to 200 CHU higher.
“Selecting a hybrid is not an easy decision and when determining regional heat units, it’s best to look at long-term averages,” said BrettYoung Agronomic & Regulatory Services Manager, Justine Cornelsen. “Basing a decision on a previous year alone could end up as a wreck.”
In 2023, the heat units as of the third week of June were well over 1,000 CHU, with some areas well over 1,300 CHU. As of the third week of June this year, most areas are 150 CHU behind 2023, the average crop being under 860 CHU.
In Southern Manitoba, the average heat units for a growing season are between 2,500 to 2,600 CHU, and as you move further north, those numbers go down to the 16,00 to 1,700 CHU range. Saskatchewan is in that 1,400 to 2,500 CHU range.
Time to Spoon Feed the Corn #
Corn takes up 60% of its nitrogen requirements prior to flowering, but it’s within the reproductive stages where the remaining 40% is utilized for grain development. Nitrogen uptake prior to flowering supports critical ear shoot development, kernel number, and potential kernel size.
Slower, delayed corn allows for the opportunity to assess if more nitrogen is needing to be applied. With continued rainfall throughout most areas in June, the potential for nitrogen losses through leaching and denitrification has been high. Depending on crop stage and plant health, a nitrogen top-dressing application may need to be applied.
“Providing nitrogen to corn when the crop needs it is not only is a better investment but also a smart choice for the environment by minimizing losses,” said Cornelsen.
With this year’s excess moisture, it will be extremely important to keep a watch for nitrogen deficiency symptoms in many crops – not just corn. Large amounts of early precipitation make for shorter roots as the plants don’t have to grow as far to find moisture. The downfall of this can be seen later through lodging plants and limited nutrient uptake.
No matter how this season ends, corn is a versatile crop when it comes to using it and harvesting it, so growers can be sure to make it work one way or another.
