By Darren Hefty
Whether it’s yield or protein content or both that you’re after, fertility is a key to top production in wheat. Here’s where to start:
PRE-PLANT
A complete soil test will let you know what you have to begin with. We send our samples to Midwest Labs in Omaha and the cost is roughly $25-$30/each for the S3C test. Then use the free Ag PhD Fertilizer Removal app for your smartphone or iPad.
Simply type in your yield goal, and the app will show you how many nutrients the crop will remove from the soil with the grain and for the stover. Make sure you supply your crop with adequate fertility at some point throughout the season. In most cases, split-applying the fertilizer will be a benefit to you, as you’ll see below. With early season nitrogen applications, using a nitrogen stabilizer like NutriSphere-N has helped keep the nitrogen in the ammonium form longer, leading to less leaching and better plant uptake.
EARLY-SEASON
You must look at your fertility program for wheat as a total program. If you put quite a bit of the fertility out pre-plant, then your needs will be much less at the later stages. However, if you didn’t put much down, here’s your chance to make up for it. It’s critical for wheat plants to get adequate fertility in the first 6 weeks of growth. Just look at the research that IPNI (the International Plant Nutrition Institute) and others have done on phosphorus.
Phosphorus is critical to early-season root development and tillering. A deficiency of phosphorus in the first 6 weeks can lead to season-long underperformance.
In winter wheat, trials comparing fall-applied nitrogen to spring applications have shown better performance with spring applications. Nitrogen stabilizers have shown positive responses in both situations. Any liquid nitrogen applications in an actively growing wheat crop should be done with a steam bar to minimize potential leaf burn issues.
Micronutrients are also important throughout the life of a wheat plant. If you didn’t put a good blend of micros down at planting time, they can be used foliar or with stream-barred applications.
IN-SEASON
Late-season nitrogen applications have been a great way to boost protein levels in wheat. The key is to use highly available nitrogen and to avoid leaf burn. Stream bar applications can be made fairly late in the season. Some will do it right up to heading.