FROM THE FARM REPORT: PLANTING CORN – HOW EARLY IS TOO EARLY?

When the calendar flips to April, I always start thinking about when it will be time to plant corn. But how early is too early? Well, that depends on your definition. Technically speaking, it is never too early to plant corn. As anybody who has dealt with “volunteer” corn knows, corn seeds are perfectly capable of surviving a whole winter out in the field – well enough to cause substantial weed pressure in a soybean crop! Even so, you won’t catch any farmer in his right mind planting corn in December. How early to plant corn really boils down to two factors: how risk averse you are, and how early favorable conditions come.

Risk Tolerance

Corn can be planted earlier than most people think. It’s just that there is greater risk for every day you push corn planting ahead of the last frost date. This is simply due to the potential for disease, flooding, frost, pests, and other problems to hit your field in the spring. But these risks are not unsurmountable, up to a point. Federal crop insurance, for example, is a risk management tool that can be used to help manage the risks of early planting. In our region, it can be purchased for any crop planted on or after April 11th, which is way before we have ever planted a field here at Miner (to my knowledge). Of course, with greater risk, there is sometimes greater reward. Early planted corn can benefit significantly from greater daylength early on, greater moisture availability during critical growth stages, and a longer total growing season. All of which can translate into higher yield.

Conditions at Planting

Planting conditions are arguably the most important factor determining when corn can be planted successfully, assuming the earliest crop insurance date has passed. Corn can survive a hard freeze reasonably well while the growing point is still underground, but it won’t survive more than a few days underwater if a wet weather pattern sets up. It also can’t outgrow the sidewall compaction that occurs if you decide to “mud it in” early. The best practice is to wait until the field is dry enough, and the soil temp is expected to be around 50 degrees for a day or two. This reduces the risk of imbibitional chilling injury, where cold water moving into the seed damages cell membranes. Once the seed has become moist, it becomes more resistant to cold injury.

Studies have also shown that hybrids vary significantly in their ability to tolerate cold stress conditions. Picking a hybrid with good stress emergence can make a big difference if you anticipate planting early, which is often a necessity if you are trying to grow the maximum maturity for your region.

In addition to stress emergence ratings, it may also be worth running a cold/stress germination test on the hybrid you plan to plant early. Standard germination tests are run at optimal conditions (77 degrees). That is unrealistic for early planting conditions. If the hybrid falls on its face when the cold germination procedure is used, it probably isn’t a good candidate for planting early. You can also try germinating some seeds in a cool basement if you would rather not pay for the lab test.

Whenever you decide to plant your corn, it always pays to get the corn planter tuned up early. If the calendar says it’s time to plant and the conditions say it’s time to plant, it’s still too early if you haven’t taken the time to properly set up your corn planter. A job done right is better than a job done early.

Note to Reader: In my February article “MANURE IS WORTH MORE THAN YOU THINK” we actually applied 30 tons/acre rather than 13 tons/acre as printed. My apologies for the typo.

— Allen Wilder

Wilder@whminer.com