The following update was prepared by Clemson Peanut Specialist Dan Anco.
In a previous notice we mentioned the importance of Boron application to avoid Boron deficiency (and toxicity) in peanuts. There are lots of different products to choose from, and sometimes the difference from one to another is not as straightforward. Typically the best way to compare similar products is to look at the active ingredient concentration and base our application amounts on the desired amount of active ingredient we want. However, sometimes the unspecified or proprietary “inactive ingredients” can play an important role as well. As an example, a liquid boron product containing 10% boron would require about 2 qt/A (58 fl oz/A for products containing 1.1 lb boron/gal) to supply 0.5 lb boron/A. Some other products advertise a “low-use boron” formulation. For example, Boron X-treme contains less total elemental boron (7.5%), but the recommended rate to provide 0.5 lb Boron comes out to be 0.5 pt/A, which is quite a bit less than recommended for the product containing 10% elemental boron. The lower recommended rate is due to the “proprietary blend” that uses an auxin hormone and another compound to increase leaf solubility and plant uptake of the boron.
To put these rates into perspective, Boron X-treme runs around $32/gal ($2 per acre for a 0.5 pt/A application), whereas its Boron 10% counterpart runs around $12/gal ($6 per acre for a 2 qt/A application). In theory, this would favor the low-use product. Since we have not yet had a chance to examine Boron X-treme in our peanut trials, at this point all I can do is help clarify the labels. The proprietary components of Boron X-treme is supposed to mix well with most products with the exception of ammoniated zinc (which in most cases we don’t need to apply to peanuts anyway) and certain calcium products (this also shouldn’t be an issue since our calcium is spread separately). If uncertain about a specific mix compatibility, mixing up a small-scale batch in a jar test can help indicate if certain products are incompatible in the tank.