Finally, harvest 2015 is about over. During this past season we have discussed what worked, what didn’t, what we need to look at next year and what needs to be discarded. One of the most consistent questions I get is about the value of foliar products on soybeans. It is a good question and I want to explore that in this blog.
There are a couple of different foliar-type products on the market. Some of them are micronutrient products of some kind, usually in a combination of multiple nutrients. Others are either a biological or “hormone” product, usually made up of some type of plant extract intended to boost yield by increasing the level of something in the plant.
Today we’ll talk about the foliar micro products that I have had some experience with. First, let me say that foliar applications as we know them today will not replace good, basic soil fertility. They can, however, supplement nutrient deficiencies in the crop during the growing season until the plant can draw nutrients from the soil. One of the best examples of this is manganese yellowing following a glyphosate application. The act by a soybean plant of metabolizing glyphosate can and often does cause a brief manganese deficiency. The addition of a foliar containing manganese often will eliminate that yellow flash and will increase yield by eliminating stress in the plant.
What we have learned in our research at Wabash Valley FS is that a combination of foliar micros at the appropriate time will consistently provide a positive return. Our best combinations will contain sulfur and iron for quick green up and manganese, boron and zinc for stress reduction. In our tissue tests over the last several years we have been able to increase the level of these in the soybean plant for a short time. This allows the plant to recover from whatever stress it is experiencing and begin to again take up nutrients from the soil as it should.
Just remember, as I said in the beginning, nothing replaces good soil fertility! Foliar nutrition is a stopgap only, a tool to mitigate stress during the growing season and keep the plant growing and flourishing. We did a foliar application of magnesium on a grossly deficient soybean field a few years ago. We then monitored tissue tests weekly for three weeks. Seven days after application we were right back in the below normal range and couldn’t bring it back up. Soil tests later showed a serious magnesium deficiency that needed soil correction.
We have had very good success using products that blend both micros and the biological aspect to increase plant health and reduce stress at important times, like flowering and pod set. But, always look at total cost per acre and potential ROI when making a decision. A $35 per acre application that improves yield 3 BPA isn’t as good a deal as a $5 to $7 per acre that hits that 3 BPA return.
Foliar nutrition can really add to your bottom line, but do your homework. Find the products that fit your operation and offer the broadest spectrum of micros that fit your geography and environmental needs. It isn’t a cure-all, but can be a useful tool in our quest for that triple digit yield.
Mike Wilson is a Specialty Products Marketing Coordinator at Wabash Valley Service Company. For over 20 years, he has been working with farmers in ten counties in southeastern Illinois to improve economic yield in soybeans, corn and wheat. Mike has been a CCA since 1994 and is looking forward to being a part of the Soy Envoy program.