I think too often people assume a deficiency is caused by not enough of something and many of the first reactions is to add more when more might not be what best. One thing to remember is that if you overfeed you can cause nutrient antagonism where you have an abundance of one nutrient that locks out another nutrient which causes a deficiency. That plant looks like it's been overfed. Adding more of anything may not be the best course of action. While most will say you need to add this and that. I am of the belief that if you have a deficiency caused by excessive levels of nutrient feeding that the best course of action is to add less. I think that plant has been overfed for a long time. You have dark green leaves that are becoming crispy fried. You even comment in another one of your posts about how dark green the leaves are. I don't believe adding more of anything is the answer. I think less is more at this point.
Many people are quick to look at that chart showing deficiencies and immediately assume it's this or that based on a picture. While the plant may have deficiency how it occurred may not be from a lack of nutrients but from an overabundance. I know people are going to disagree with me but I think your issue is being caused by overfeeding that's been going on for awhile. For instance, too much nitrogen can lockout potassium, adding more potassium can affect phosphorus and calcium, adding more of those can affect other nutrients. Do you see where I'm going with this?
I even have this for my signature.
"The overfeeding of any plant food can cause nutrient deficiencies."
"Deficiencies can occur if one or more minerals are in excess. This may seem contradictory, but many elements have antagonistic effects on others. These antagonistic nutrients are often ions with the same charge, and occur when one is in excess in a solution or in the soil. If one is in excess, it will block the uptake of another, therefore causing a deficiency and affecting crop quality and yields."
By Shara Ross RX Green Solutions Plants require a variety of nutrients to achieve optimal growth, yields and quality.
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