Originally Posted by Kiril
Once again ... no one is twisting anything here quack .... and if you were to take a honest look at your post and how it was presented, you would see the numerous problems with it.
My post is fine, its your interpretation that is the problem.
You are trying to dismiss the fact that nutrient input can be minimized by using organic and synthetic fertilizers to better follow demand curves.
The only argument you have is insisting that the word optimal means the most growth. That is like saying optimum mowing height is the most you can cut off, or that optimum irrigation causes the most growth.
Its pretty easy to understand that optimum is "the most favorable", and therefore changes depending on what you're looking to accomplish. The optimum diet for an athlete will be different than the optimum diet of an obese person.
I know that sometimes you use fertilizers to add nutrients, and the rates and objectives are different for each site and vary from plant to plant. What you are trying to achieve is the most favorable condition for the plant. That could mean limiting growth or expanding it.
Lets say you are going to fertilize because a plant is deficient in nitrogen. You establish that it will need 1lb of N per K to get it back on track without causing excessive growth.
If you use 1lb of an organic N source it will provide enough nitrogen to relieve it of deficiency even during the plants peak demand. However, if it can accomplish that during peak demand, then it will likely be excessive during the rest of the season when Nitrogen is not in demand. So now you have excessive nitrogen for a good part of the season which increases leaching and costs.
Another option would be to use .5lb of an organic nitrogen source because that will better suit the plants demand over the majority of the season, but it would leave the plant overly starved during the peak demand period.
To keep the plant from being deficient at that time you could add .25lb of synthetic N just before peak demand, the plant would absorb it and then rely exclusively on the organic N for the remainder of the season.
The result would be less nutrients, cost, and leaching.
Another attribute of synthetics is that you can pinpoint just the nutrient that is needed and apply it when the plant is going to use it without adding things the plant wont use.
It may not seem like a big deal to somebody that uses a pallet of fertilizer, but say you use 10 semi loads - tailoring nutrients to the demand curve means you can potentially delete a couple truck loads of fertilizer per year.