Fertigation vs slow release granular fertilizer (blueberry)

General Fruit Growing
1

I know most of you grow blueberries non-commercially but still I would like to know your opinion about this:

“Liquid fertilizer should be applied to blueberries by incorporating it into the watering program once per week. Irrigation water should be allowed to run for one hour to fill the irrigation system and moisten the soil at the root zone. The recommended amount of fertilizer solution should then be introduced into the irrigation water for one or two hours and, then, fresh water applied for one hour. This method allows the system to fill with water and moisten the ground, allow the fertilizer to be applied, flush the system of salts and wash the nutrients into the root zone.” https://articles.extension.org/pages/29218/fertigation

This seems to me to be the greatest advantage of fertigation. For about a couple of days I have been reading about salinity effect induced by any N source as fertilizer. And frequent irrigation seems to be efficient in leaching the salts away…

But if you use slow release granular fertilizers it is not that easy to leach those nitrates and sulfates away right?
Apart from studying the salinity effect of various N sources like ammonium sulfate or urea, and engineering (or trying) a ratio of them to ensure more or less least salinity effect along with least ph change, how can one achieve this flushing of salts from the root zone without fertigation?

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I have always had a logical issue with the advantages of flushing away the salts. My issue is if the salts are flushed away, what else are you losing? Seems to be you may be losing other unmeasured nutrients as well. The only way to avoid salts is to not introduce them in the first place. Being non-commercial I have that choice.

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3

True. In our own bodies some things we take in are fat stored, other stuff goes right out of us. I am certain that a negative of watering a lot is loss of some nutrients, or micronutrients, but then growers just have to do soil tests to find out what needs replaced.

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