Corn School: Weighing the risks of pushing hybrid maturities


How does adding 100 crop heat units to the maturity of your corn hybrids impact the yield and profitability of the crop?

Agronomist Peter Johnson tackles that question on this episode of the RealAgriculture Corn School with help from University of Guelph associate professor David Hooker. Earlier this year, Hooker took a deep dive into Ontario Corn Committee performance trial research and crunched data from 42 site years. He found that when growers planted hybrids 100 CHU above the full season rating for their area, on average the crop yielded an extra 6.1 bu/ac. And even though these crops were an average 1.2 per cent wetter, there’s certainly profit in going long.

But is the potential profit in that 100 CHU leap really worth it? In the video, Johnson notes that when Hooker published the data on Twitter, many growers questioned if pushing hybrids was worth the risk, especially in short-season growing areas of Ontario. “One hundred heat units doesn’t make a big difference in higher heat unit areas of southwestern Ontario — they’re already growing long-season hybrids,” says Johnson.

Moving from 2600 to 2700 in more northern growing areas, however, creates challenges, says Johnson. He points out that many farmers chiming in on Twitter said they understand the economics but “if you don’t make it, you’ve got low testweight corn,” says Johnson. “There’s also a mental health benefit of not having to fight mud, avoiding compaction and not having to listen to Christmas music in the corn combine.”

Some growers noted there are ways to mitigate risk while also capturing some extra bushels. Johnson says one way is to push a small percentage of short season acres — 10 to 20 per cent  — to a higher maturity.

Click here for more Corn School episodes.

Other Episodes

Corn School (view all)Season 11 (2022) Episode 1

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