New to Jacks - what's the skinny?

Hello folks, been awhile since I needed advice. This forum has helped me tremendously in the past and I’m looking for your help again. I’ve recently put aside the Fox Farm Trio, which I have had good results with. Now I am jumping on the Jacks 321 band wagon, but I have no idea what I am doing. It’s a whole new ball game to me. All help is appreciated, thanks in advance.


Real simple stuff. Frequency will depend on if you’re growing in soil or coco. The jacks web site has feeding schedules :love_you_gesture:


I only grow with HP Pro Mix, kind of soil without the soil LOL.

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Jacks is simple 3 parts A, 2 parts B And 1 part Epsom salt. 3.6 grams to 2.4 to 1.2 grams. Just asked about measuring myself since my digital doesnt do decimal in grams.

Per gal of water. Simple just to use 3 g, 2g, 1g. Mine has abt 1250 ppm when i do it that way.

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This is my fourth delivery from my new hobby. Seeds, lights, pot 4 pot, and jacks nutes just arrived.

Jacks is the only one to display their name on package. We arent legal state.

Hopefully, they dont know Jacks.

Jacks rounds up to 4 grams as per directions.

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And these tiny hand prints, child labor laws to protect from this.


We got our stickers paid for them. But we got them.

Total 2.2 lbs each. Approx 55.00 on both and 30.00 in shipping straight from Jacks
Still, no complaints on cost.


You can get some pretty good deals on 8 lb kits on ebay or 4 lb kits just some food for thought probably cheaper it’s just repackaged by somebody out of a big package :v:


I just ordered my 2nd batch of Jacks from ebay 6lb kit for 31.00 +/-


What kind of water are you using? My tap is at 170ppm. When i add, silica, then jacks at 3.7/2.2/1.1, with a ¾ dose of Fox Farm dry nutes, my PPMs only hit 1130ish.

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@Borderryan22 im around the same after mixing jacks in my RO no tap and nothing extra except silica at 6ml for 5 gal. Im going off of 3.6 part a, 1.2 epsom salt, and 2.4 part b


Ive been using Jacks for the past few grows. I mix in 5 gallon buckets and mix in this order.

  1. Si (2ml/gal)
  2. jacks part A (19g)
  3. epsom salt (6g)
  4. jacks part B (11g)
  5. Big Bud (week 2-4 of flower) (8ml/ gal)
  6. Bud Candy (all through flower till flush)(8ml/gal)
  7. ph
  8. Fish!t (2ml/gal)
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How many different formulas did we get. 5 or 6. Damn confusing.
The 3.6 / 2.4 / 1.2 is what I call the conventional formula.
The 3 / 2 / 1 formula is referred to as the “literal” formula
My recommendation is to start with the published feed schedule recommended by JR Peters (Jacks)
www.jacksnutrients DOT com/cannabis-hemp-schedules


Those 19, 6, and 11g measurements are for 5 gal of mix which is the 3.6, 1.2, and 2.4 formula… just to clarify. Sorry if that was confusing.

Must be 3.8, 2.2, 1.2. ? @Sydious

You are correct… thank you sir. 3.8 not 3.6… math, mornings and work don’t mix well in my addled brain!:crazy_face::rofl:

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Tap is 145ppm. 7.0 ph