As we approach the beginning of 2020, we should reflect on the history of crop nutrition and where we have come from and are going to. With the use of fertilizers, we have seen a drastic increase in the yields of our crops, especially in the last 20 years. We have seen 30-bushel canola crops being the goal to 60-bushel crops being the standard in some areas. While this drastic increase has been a combination of factors such as better crop nutrition, more crop nutrition, and better plant genetics, one must think that there is more that we can do. Immediately when a person says more, we begin thinking of adding more pounds of fertilizer, but that doesn’t always have to be the case. We still must consider Liebig's Law of Minimum when contemplating crop nutrition plans. More isn’t always better. In fact, more can end up being wasteful. We must take into account that everything needs to be in balance, from macronutrients to micronutrients.
Liebig's Law of the Minimum
Many factors need to be considered when developing well-balanced crop nutrition plans. These include soil tests, tissue tests, observations, and arguably the most important agronomic absolutes. Agronomic absolutes are simply taking a look at what the crop needs of each nutrient to grow throughout the season on a per bushel basis. An example would be a canola crop requiring 3 lbs of nitrogen per bushel or 1 lb of phosphorus per bushel to grow. For the macronutrients, we have these measured in pounds, whereas micronutrients are required in grams. We should consider crop needs and how the crop will access these nutrients. Soil only? Additional soil-applied fertilizer? Foliar fertilizer? How do I feed this crop throughout the season, while balancing economics, and logistics to provide me with yield and quality I desire?
We should also consider what we already know. It's important to move from being reactionary to micronutrient deficiencies and scrambling to go in with a foliar, or “getting it next year”. If we know there is a specific nutrient that is deficient, why not be proactive about it, ensuring this nutrient is part of the crop nutrition plan? By understanding crop needs and which micronutrients are the most vulnerable, you can come up with a plan to ensure sufficiency of the nutrients for that crop. Using our previous article on deficiencies in Western Canada, we can start to anticipate what may be issues to look for. Couple this with your soil tests, tissue tests, and observations and you can begin to be very proactive in balancing your crop nutrition plans.
In the end, you can think of it like your favorite Grandma's bread recipe. It takes, among other factors, the right amount of all ingredients for the result to be the best possible. The same goes for crops: all required nutrients need to be available, balanced, and in the right amounts for growing the best possible crop.
Contact your local Yara representative to learn more about micronutrient needs.
Cody Vogel, Sales Agronomist - Northern Alberta