Where do you buy this stuff? I’ve check their website but it’s more than just 321 so now I’m lost. Any help please?
I get mine off eBay 6lb kit.
Okay, the a b and Epsom?
Yes about 33.00
@Cfpdadto3 Amazon has a selection
https://www.amazon.com/s?k=jacks+321&ref=nb_sb_noss?tag=greenrel-20
edited to add tag to link
Check at grow green Michigan website. They sell Jacks at a discount, and have all of Jacks products.


Growgreen MI is out of stock.
I checked amazon - too expensive.
Jack’s A & B pictured is from Esbenshades Garden Centers
Go to walmart cvs or walgreens for epsom salt
They routinely deeply discount Jack on their eBay store for a day or two.
Nearly half price at times.
When I changed over I ordered from Amazon. Ordered the big bags of A,B and Epsom Salt. Ive got enough for 900 seeds I think!!!
Amazon. I bought 25 pounds of a and b for 150$
Just looked at growgreen Michigan website, they have it in stock, and 25 pounds of A & B is $119 with free shipping. Also the 2 pound bags are $20 each.
Quick question with the jacks gang. Im using tap water so i got the part A recommend for it.
Instead of 321… should i be using 5 2 1? Am i reading correctly ![]()
I use tap water and RO water. I use a, b and Epsom salt. If you get the one made for tap water (15-5-20) thats all you need if I’m remembering right. It’s an all in one nutrient. You don’t need part b. Some people say add a little epsom salt, but it’s supposed to have all the magnesium you need. So you just add 5.05 grams per gallon and you’re good to go.
@Ickey has you covered ![]()
The schedule you posted is for 15-5-20. This is referred to as Jack’s TAP formula. It is designed to be used with tap or well water.
For a gallon of mix use 5 grams of 15-5-20 and 1 gram of epsom salt. Mix thoroughly, ph, check ppm and adjust accordingly.
It is not the common 321 formula
did not know that. When I first switched to Jack’s 321 I searched and it had the best price with shipping for 25# bags. I try to find what I need locally first then anywhere but amazon if I can.
A while ago I did the math. How many gallons can I get from 25# bags using 3.6 / 2.4 / 1.2 grams per gallon. I rounded and used 450 grams per pound

Awesome. Appreciate it man
@beardless I like your local first approach. I only buy from Amazon as a last resort also. Hate the way they let the vendors lie about the products, and take advantage of the new grower.

