Jacks 321 and optimal hydroponic nutrients

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anarchov

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I am new to the forum and growing cannabis, but not new to hydroponics. I used to operate a commercial hydroponic lettuce farm (NFT) where we grew about 1000 lbs of lettuce per week. While operating the farm, our nutrient regimen was backed by some pretty solid research of optimal hydroponic solutions that included ppms of each chemical element. I have a lot of this research for lettuce, tomatoes and cucumbers but not for cannabis. We used all dry fertilizers in our operation due to the cost savings and I hope to switch to the same with my cannabis grow (I just started growing with the most readily available liquid nutes in my rural area, fox farm, a year ago).

I have been looking at Jack's 321 and crunching numbers on nutrient ppms based on their recommended rates per gallon- 3.7g part A 2.5g part B 1.1g MgSO4:

N151.24
P117.29
K254.13
Ca125.48
Mg28.48
S37.49
B0.49
Cu0.15
Fe2.93
Mn0.49
Mo0.19
Zn0.15

I also stumbled across this research paper: https://www.preprints.org/manuscript/202108.0460/v1
To summarize the study- "Based on the results of this study, we recommend providing plants with a nutrient solution containing N and P at approximately 194 and 59 mg L-1 , respectively, to achieve maximal inflorescence yield." Optimal K supply was found to vary based upon cultivar.

While this is just one study and is far from conclusive, has anyone experimented with lower P rates and higher N rates with success? I will probably just start with the standard feed suggested by Jack's 321 but was curious if anyone had any real word experience with reducing P rates.
 
delps8

delps8

31
18
I am new to the forum and growing cannabis, but not new to hydroponics. I used to operate a commercial hydroponic lettuce farm (NFT) where we grew about 1000 lbs of lettuce per week. While operating the farm, our nutrient regimen was backed by some pretty solid research of optimal hydroponic solutions that included ppms of each chemical element. I have a lot of this research for lettuce, tomatoes and cucumbers but not for cannabis. We used all dry fertilizers in our operation due to the cost savings and I hope to switch to the same with my cannabis grow (I just started growing with the most readily available liquid nutes in my rural area, fox farm, a year ago).

I have been looking at Jack's 321 and crunching numbers on nutrient ppms based on their recommended rates per gallon- 3.7g part A 2.5g part B 1.1g MgSO4:

N151.24
P117.29
K254.13
Ca125.48
Mg28.48
S37.49
B0.49
Cu0.15
Fe2.93
Mn0.49
Mo0.19
Zn0.15

I also stumbled across this research paper: https://www.preprints.org/manuscript/202108.0460/v1
To summarize the study- "Based on the results of this study, we recommend providing plants with a nutrient solution containing N and P at approximately 194 and 59 mg L-1 , respectively, to achieve maximal inflorescence yield." Optimal K supply was found to vary based upon cultivar.

While this is just one study and is far from conclusive, has anyone experimented with lower P rates and higher N rates with success? I will probably just start with the standard feed suggested by Jack's 321 but was curious if anyone had any real word experience with reducing P rates.
I'm getting some different numbers than you. This is 3.79-2.52-0

N as nitrate 150
N as ammonium 0
N as urea 0
Phosphorus (P) as P2O5 52
Potassium (K) as K2O 216
Calcium (Ca) 140
Magnesium (Mg) 89
Sulfur (S) 116
Iron (Fe) 3
Boron (B) 0.5
Manganese (Mn) 0.5
Zinc (Zn) 0.2
Molybdenum (Mo) 0.1
Copper (Cu) 0.2
Cobalt (Co) 0
Silicon (Si) 0
Sodium (Na) 0
Chlorine (Cl) 0


I've read that paper and there are lots of others that provide hard data on nutrient levels. My take on it is that cannabis does well under a range of nutrients. I've used bottled nutes for three grows (hydro) - one was Fox Farms and two with Botanicare Kind nutes. I've switched to Jacks 3-2-1 and I mix it as 3.79-2.52-0. I don't add Epsom salts because there's enough Mg and S already.

In my Botanicare grows, I had some deficiencies and constantly dropping pH. I was constantly adding Up. For my current grow, using Jacks 3-2-0, I'm in day 36, the plants look great, and the only issue I've had is that I've had pH drop from 5.8 to 5.7 twice. In each case, I added 1.5 CC Up. That's it in 5 weeks. Granted, that's just seedling and veg so there's plenty more time to go but, so far, it's been completely uneventful. I'm very glad I switched from Botanicare to Jacks.

I switched from Botanicare for four reasons - their website and support on the site are atrocious; at the end of my last grow, I needed one of the nutes and I discovered that it could no longer be sold in here in the People's Republic of California, the pH swings were driving me crazy, I got help from someone who shared some knowledge of calculating elemental PPM's and it was clear that I was paying a huge premium for a shipping bottled water.
 
Peat_Phreak

Peat_Phreak

540
143
I'll make it easy for you.

1 part Jacks 5/12/26
1 part calcium nitrate
zero epsom salt

This ratio can be used for the entire grow. Adjust to the desired EC for each stage. NPK is approximately 4-1-6. Cal mag ratio is 3:1. That's the basic nutes. A few extras like silica and fulvic acid are a good compliment.

Results are in my grow thread.
 
Dr.Green55

Dr.Green55

577
143
I am new to the forum and growing cannabis, but not new to hydroponics. I used to operate a commercial hydroponic lettuce farm (NFT) where we grew about 1000 lbs of lettuce per week. While operating the farm, our nutrient regimen was backed by some pretty solid research of optimal hydroponic solutions that included ppms of each chemical element. I have a lot of this research for lettuce, tomatoes and cucumbers but not for cannabis. We used all dry fertilizers in our operation due to the cost savings and I hope to switch to the same with my cannabis grow (I just started growing with the most readily available liquid nutes in my rural area, fox farm, a year ago).

I have been looking at Jack's 321 and crunching numbers on nutrient ppms based on their recommended rates per gallon- 3.7g part A 2.5g part B 1.1g MgSO4:

N151.24
P117.29
K254.13
Ca125.48
Mg28.48
S37.49
B0.49
Cu0.15
Fe2.93
Mn0.49
Mo0.19
Zn0.15

I also stumbled across this research paper: https://www.preprints.org/manuscript/202108.0460/v1
To summarize the study- "Based on the results of this study, we recommend providing plants with a nutrient solution containing N and P at approximately 194 and 59 mg L-1 , respectively, to achieve maximal inflorescence yield." Optimal K supply was found to vary based upon cultivar.

While this is just one study and is far from conclusive, has anyone experimented with lower P rates and higher N rates with success? I will probably just start with the standard feed suggested by Jack's 321 but was curious if anyone had any real word experience with reducing P rates.

Well really the individual PPM numbers are insignificant, Ratio's of nutrients in the solution is what your trying to maximize. understand that is how you build a solution from dry salts, those ratio's are going to be derived by environment, lighting, temps RH etc etc, also by strain, medium and so on. So really you start with a nutrient solution baseline and adjust as you go to dial it in to your room grow style etc. . You said about running High N well its no good to run more N them what your lights can handle, if you do your done before you start, lights, temps nutrient flow rate etc will tell you how much N you need, but there is a ratio of N to K to Ca where if one is to out of balance you'll have antagonistic issues, the K to Ca to Mg is very important as well, but thats goes for all your nutrients. you can push N a bit but your going to have to have Ca at least equal to but more likely higher then N to control N tox. P is going to be about balance all the same and the ratio it has with the other elements.

If your talking veg mix for what you posted if you want to start with that much N I'd up Ca and bring K down a bit, you don't need as much k in veg as flower and you want Ca in veg then flower. you can run P at 50-60 ppm the way through veg and flower with outstanding results in a balanced solution,. your Mg and S is far to low especially if running LED's . then you can adjust the solution for pre-flower and flower.

those are just some very basics but the key to mixing your own nutrients is having a good understand of how each element works in the solution, interacts with one another, needs one another but can easily become antagonistic with one another if not in a balanced ratio. and remember your setup/environment will dictate on how your plant like to be fed.

you'll also need a good understand of how to read your plant, by looking at the leaves, feel, smell colors etc. the closer the nutrient balance matches your environment the better these will all be. You can get into to brix tests as well, if you don't have a good understand of what i just mentioned though you may just end up chasing your tail. But it can help adjust Ca etc. but you can test your sap and see what your brix is, if it low you know you need to adjust , but you can play around with foliar spraying each element and see how it reacts, if positive you can then change that element in the solution.

good luck
 
I

Its420anytime

55
18
321 is pretty simple 3 parts to 2 parts to one part =321 to a gal.
I like simple. Used to be 3.6. 2.4. 1.2 grams straight coco and jacks and nothing else but good lights. 2.2 lb bags of jacks of esch will last a the rest of my grows. No flushing needed
 
B

biscayne348

2
1
Is it okay to mix classic jacks with 321 for veg or flower?
 
CookiesLikeWhoa

CookiesLikeWhoa

220
63
When you say "classic jacks" what are you referencing?

The 3-2-1 in Jacks 321 is:
Jack's Part A: 3gr/gal
Jack's Part B: 2gr/gal (Can be subbed for any Cal Nitrate)
Epsom Salt: 1gr/gal

Either way you can run this 321 straight through veg and flower.
 
B

biscayne348

2
1
When you say "classic jacks" what are you referencing?

The 3-2-1 in Jacks 321 is:
Jack's Part A: 3gr/gal
Jack's Part B: 2gr/gal (Can be subbed for any Cal Nitrate)
Epsom Salt: 1gr/gal

Either way you can run this 321 straight through veg and flower.
I am referring to the Jack's classic All Purpose 20-20-20 and blossom booster 10-30-20 water soluble food. That's what I have been using until recently I have tried Advanced Nutrients along with Jack's classic.
A representative of Advanced nutrients cringed and stopped trying to convince me of their products after I said I use Jack's classic. Advanced nutrients has to many parts and gimmick additives.
 

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