Wheat, Micronutrients and Liebig’s Law
Micronutrients are required for optimum crop production and the term micronutrient refers to the relative quantities required for plant growth and does not mean that they are any less important to plants than other nutrients. Wheat growth and development may be retarded if any one of these elements is lacking in the soil or if a nutrient is not adequately balanced with other nutrients. The total amount of micronutrients required for a 3-ton wheat yield is only 1.7 kg. That’s why it’s easy for people to say, “Micronutrients are not a big deal.” That is also what gets a lot of people in trouble.
For example, a farmer has fertilized with N, P and K for a 3-ton yield but only have enough manganese (Mn) for a 2.5-ton crop. The yield will then only be 2.5 tons! Now, think about all the money invested in N, P, and K, besides all the other costs got on the farm. If the farmer would have invested $9.00 in micronutrients, the planned 3-ton yield may have been realised. Although micronutrients may not be the most important issue on the farm, nor are they often the biggest yield-limiting factor, if you don’t have good micronutrient levels, you absolutely will restrict your yield potential. This is called the law of the minimum. Off course micronutrients may not be the most limiting factor, we all know what happens when water is the most limiting factor!
(Adapted from http://www.agphd.com/ag-phd-newsletter/2011/11/10/micronutrients-for-wheat/).
Liebig law of the minimum, often simply called Liebig’s law or the law of the minimum, is a principle developed in agricultural science by Carl Sprengel (1840) and later popularized by Justus von Liebig. It states that growth is dictated not by total resources available, but by the scarcest resource (or limiting factor).
(https://en.wikipedia.org/wiki/Liebig%27s_law_of_the_minimum).

Figure 1 Liebig’s law illustrated with a barrel, indicating the limiting factor will limit yields
There is a flip side, however. Micronutrients are cheap, so it is easy for the farmer to just dump a bunch out there. There are two problems with such an approach:
- These microelements may now be excessive in the plants (and soil) and become toxic
- Excess of one nutrient can lead to reduced availability of other micronutrients (and even macronutrients), so there will most likely now be a shortage of something else in your plants.
Therefore, pick a blended micronutrient product that is right for the crop, and use what you need each year. That will keep your micronutrients in balance in the soil, and it will most likely keep your crop from being yield-limited from a lack of micronutrients. This small investment of only a few dollars per hectare will often pay you back many times over.
(Adapted from http://www.agphd.com/ag-phd-newsletter/2011/11/10/micronutrients-for-wheat/).
Nutrimix® Complete
Numerous studies have shown the foliar application of micronutrients on wheat increased tillering ability, spike length, grain yield and the quality of the wheat. You can apply micronutrients pre-plant or at planting-time with our Novatec® N-Max fertilizer, or as a foliar application with our Nutrimix® Complete micronutrient product.
Nutribor®
For boron demanding crops (oil crops like canola, sugar beets, cotton, etc.) and boron deficient growing conditions (sandy soils, high pH, etc.)
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