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Supplement CAL MAG ?
CaptainCreamstarted grow question 6y ago
If I had a Cal & Mag deficit and replenish it with liquid supplements after about a week, will the plant recover? If so, after what time?
or Maybe you think its something else? NOT CAL MAG ?? Help me ... ;)💩
Solved
Leaves. Color - Yellow
Leaves. Color - Dark-brown
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Athosanswered grow question 6y ago
Calcium deficiency shows on newer leaves, not older ones so it is not that. It looks like a textbook magnesium deficiency, but there's a few thing you need to keep in mind before rushing to buy cal mag or similar. First magnesium absorption is locked out when you overfeed potassium (K) or phosphorous (P) (flowering nutes) so be sure it is not an issue of overfeeding; also magnesium deficiency exists 4 to 6 weeks before it shows like in your pictures, so it will take a while before it looks like it is getting better. Your source water needs to be around 0,5 EC (250 PPM), if it is much lower, then you will have to supplement calcium and magnesium.
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