At this time of year, it is important to start thinking about making another pass on corn fertilizer, especially nitrogen. Corn will be knee high soon, which means that it will need adequate amounts all nutrients to make sure you get the most yield out of your crop.
At V5-V7 stages, a corn plant is at the perfect maturity to start the application of nitrogen fertilizers. Applying nitrogen during the V5-V7 maturity stages is important because corn takes up around half of its nitrogen supply during the V8-VT stages. Nitrogen plays an important role in green tissue formation and ear fill in corn. Below is a graph depicting a corn plant’s nitrogen uptake and usage during its maturity stages.
From V8-VT, corn uses over half of its available nitrogen for green tissue formation and plant growth. It is important to make sure that a corn plant has the nitrogen it needs so that it can continue to grow at its normal, rapid, rate.
In addition to green tissue development, nitrogen is also instrumental in ear and kernel development. By the time corn reaches the R1 stage, it has been much too tall for far too long to think about a sidedress application of nitrogen. That is why it is important to provide the plants with adequate amounts of nitrogen during the short window of opportunity presented during the V5-V7 stages of development. If done under correct weather conditions, a sidedress nitrogen application during the correct stages of development can provide a corn plant with enough nitrogen to carry it all the way through ear and kernel development.
To recap, if supple nitrogen is available for corn during the V8-VT stages of development, you can maximize yield production. With nitrogen playing such an important role in both green tissue development and ear and kernel development, it is a necessity to have enough of it to allow your corn to thrive and really show its high yield potential.
Tom Arndt