The In's and Out's of Fishbone Meal

  • Thread starter SweetLeafGrow
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I was searching the forum for some information on fishbone meal and found that this topic has rarely been discussed. I figured I could bring it up and see if any cultivators are using this great organic source of Phosphorus. I will post what little bit I know and hope that others with knowledge in this area will offer up their expertise!

So, being the new grower that I am, when I first decided to get my feet wet, my wife and I both agreed go organic. A friend advised against it, but onward I went into the world of organic cannabis. I ended up buying Coast of Maine Platinum blend soil, but was unable to get their suggested amendments in their product line because they were unavailable. I found an organic veg blend to substitute and then for bloom, they were recommending their Coast of Maine blend of fishbone meal, again, both unavailable unless I wanted to pay twice the MSRP. Coast of Maine recommends using their fishbone meal at the beginning of week 1, 3, and 5 at the rate of 1/4 cup for 5 gal container. Simple enough.

After reading about flowering cannabis, I decided that I did not think the straight up fishbone meal I had bought would be everything the plants would need to take them to harvest. For example, their NPK did not include any Potassium at all. So I ended up getting some Roots Organics Terp Tea Grow and Bloom, which I have been using after the first 30 days of veg and the soil was depleted. These have been working good but I was thinking of adding some of the fishbone meal in addition to the Terp Tea Bloom I am now giving, just starting the 2nd week of flowering and 12/12 lighting. Here are some specifics in my grow-

Flowering Nutrients I have available-
Roots Organics Terp Tea Bloom 3-7-4
Organic Fishbone Meal 4-16-0

I have some options-
Top dress with one or both of these, and water through
Top dress with one or the other and make tea with the other and water through
Just water with tea made from these two ingredients along with some worm castings and molasses

I wonder if the Phosphorus content would be too high and burn the plants if I used both of these together? Perhaps the option is use both at 1/2 strength? Using as a top dress will, the way I understand it, cause the nutrients to slow release over time, where a tea makes the nutrients readily available. I have read that a P boost during flowering is good but don't want to overdo it or give it too soon.

What do those with experience using fishbone meal have to share? Can't wait to hear!
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