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Humic Acid Buildup on my Plants and how I cleaned them


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I don’t know how often if at all you guys have experienced the problem of Humic Acid buildup on your plants. I searched the forums and didn’t find anything here about it in a cursory search. Maybe your peat is different enough there that you don’t get it wicking humic acid as much. The problem is unique and new to me so I didn’t know what it was when it first showed up on plants. But quickly I found the problem and with some help from others on the terraforums so I wanted to share my experience here if it helps at all. 

NOTE: Quote box messed things up and put everything in one square. First part is a quote from Joseph Clemens explaining the problem and then the rest is my text and me talking about my plants that had the issue and how I went ahead with the recommended treatments and shared the pictures. The quote box covered the rest of the post for some reason and made everything look like a quote and not from me.


Problem explained here really well by Joseph Clemens:
This is something that was reported on, I believe, back in the 1970's. Here is a short description of the issue.

The darkening of the growth point, as shown by the photographs shared here, is caused by humic acids, and perhaps other solubles, wicking up and depositing themselves, first on the hairs and stipules of the leaf primordia, eventually covering the entire surface of the growth point and leaf primordia. My experience is that this can have a damaging effect on the growing point and can supress new growth. The easiest way to reduce this is to gently provide overhead watering with warm, purified water as often as necessary to reduce this precipitate. Another solution would be to use less peat moss, since it is a strong source for the most offending compounds, though other media ingredients may also be sources. It is also affected by temperature, ambient humidity, air movement, etc.

I then put into practice what Joseph recommended and here is what I did:

Using a turkey baster, I gave each plant a warm distilled water bath right at the growing point and then a gentle swabbing with a Q-Tip. Check out the tremendous improvement! Thank you to Nimbulan, Not a Number, Joseph Clemens and Aaron at GrowSundews for the help with their resources on solving this issue and fixing it. I am very delighted with the results and will watch for wicking happening again and will flush the pot out even more if needed. Thanks all! :D

Here are my before and after images of the affected plants:


Edited by Odysseus
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