Hi folks. I’m a Jack’s 321 user who is curious to start dabbling in mixing my own fertilizer. I have no problems growing healthy looking plants but, that said one of the things that i’ve seen in most of my grows with Jack’s is dark-ish leaves. Decreasing CalNit seemed to be the obvious choice but it never got the result i was looking for. After reading some threads here, it looks like i’ve been barking up the wrong tree. I still need to re-read the fertilizer threads to abosrb the info better. For starters, am I correct to assume the limiting factor when using Jack’s 5-12-26 not being able to get the correct N and Ca ratios because of the amount of KNO3 in their formula? I’ll also mention that i’m growing in DTW Coco and @SeymourGreen 's thread has been incredible helpful.
To start i’m going to purchase:
MKP
SOP
PlantProd chelated micros
Calcium Acetate
Already have:
PureCal CalNit
Mag Sulfate
Fulvic acid
I’m going to start with @emdub27 's suggested ratios listed below and tweak from there.
1N:2K
1Mg:2-3Ca
1N:.65P
If i’ve missed anything please let me know.
Nice to meet you all. I’ve enjoyed the threads i’ve read so far.
Hello, First post Here after registering a while back. Used Jacks Decades back in ornamental and Veg and now they don’t sell to my state any longer. As a semi professional Hobbyist Jacks has been Really easy to mix and go and get great results, But I’m listening to cure problems I have been blaming on other factors. For one I know I have been getting some toxicity by using a large reserve and letting it get into the 1400ppm area. but My girls never seemed to mind.
Now I am just seeing numbers like under 300ppm before flushing are recommended.
I like pure hydro for the speed and space it can be pushed into for breeding out stable lines.
But favoring a Mycorrhizal peat blend for improving taste.
BUT alas I need Bulk prices to continue my mad science at scale.
You should get on the grow forums and do bunch reading
One thing I found out that no matters where u go everyone has “their” own way. All of em skin the cat just w different means
Give the plant what it needs, sometimes more is less with growing. To much nutes can be a problem
When your ready to make bho this is the place to be
Thanks. I’ve been pretty succesful over the years with Jack’s and am just looking to try something new and fine tune my grow. I thought mixing my own nutrients would be a decent place to start.
I love jacks been using for while with great success. I looked into blending my own nutes but it’s a little time consuming for me. Jacks seems like the best option to mixing your own for sure tho
Indoor cannabis gardens and techniques vary so widely that it’s pretty much impossible to write down nutritional numbers and expect a positive outcome. If you’re experienced with Jack’s, clone it and make small (5%) changes to one ion at a time, observe for about 2 weeks and if you like the changes to morphology leave it that way. If you’ve used Jack’s for some time consistently in your environment, you have a good data set that you shouldn’t abandon. Trying to dial in gardens without tissue or sap data is incredibly hard.
Thanks for the reply. That sounds like a pretty solid approach. It also looks like an easy enough formula to copy as well. I’m assuming it would be better to use individual chelated micros instead of something like Plantprods chelated micros? Short of sending in tissue samples, would a brix refractometer help with dialing in the garden?
Hello @jguit . Think I recognize your handle from the Farm. To answer your question, individual chelated trace elements are the way to go but, your going to need a precision scale to weigh them out unless your mixing for a fairly big reservoir. Mixing your own salts is relatively easy but what emdub27 said is pretty accurate. Everybody’s got a million recipes. Most of them probably grow decent plants. The ratios can be all over the place. Environment is incredibly important. I’ve was chasing my tale on my current run until just recently. Growing clones of the purple poison cookies from the previous run. Was using the same ratios from last time. The plants loved them last run. The clones of the same plants hated the ratios the moms they were taken from loved!?!? I couldn’t get my K to N ratio right for shit! Still can’t get them past five leaflets. I’ve tried 1:1.5 N to K. 1:2, 1:1. Nothing was working. I’ve adhered strictly to 3-2-1 K:Ca:Mg ratio until a Mg deficiency appeared. Then I went 4-2-1. I’ve tried 3-3-1. Nothing helped that either. I’ve run Ca as high as 225 ppm and as low as 125 ppm. I’ve run P anywhere from 50 to 85. I’ve read everything from cannabis front loads P at then beginning of the growing cycle and nothing more than 30 ppm of P is needed throughout the plants while life cycle. I’ve also read that 80 ppm of P is needed to help transport micros. I’ve also read that anything over 60 ppm of P will lock out micros so who knows? I did buy a brix refractometer and discovered my brix sucks balls! It’s only at a 2! I apparently also have a Ca deficiency at 201 ppm per gallon because it’s a hard division between the blue and white line! I guess what I’m trying to say is mixing salts is the easy part. Dialing it in to your particular set up and environment with out access to constant laboratory tissue analysis or pretty much what emdub said, is the hard part.
I have been tinkering with the idea of making a mix based off of graphs of plant tissue analysis I found on line. I know it’s not a one size fits all but it’s a starting point.
Not sure what you nitrate number is, but it’s probable that you’ve gotten to a point that Ca is antagonizing nitrate. The nitrate brings water with it that helps transport Ca.
The hard line on the brix meter only tells you how differentiated the sap ion are. Typically a high Ca sample is highly differentiated, but not always.
It’s entirely possible to have hard line 2% brix with tissue analysis that says 2%N, 2%K and 5% Ca. That’s pretty bad.
I don’t even understand brix enough to know why this is bad or, how to fix it.
I have no idea on how to raise brix. All I can find on the net is to increase K to raise brix levels.
Right now going into second week of 12/12, my N is at 175 ppm and Ca is at 203. P is at 55. K is 222 . Mg is 65 and S is at 86.
Temp is 83 F. Rh 71%. I just sprayed them at lights out with the Ca acetate foliar you told me how to make. They look way better since switching to 12/12.
Yes, I remember you from the farm as well! I see you’ve been busy. Nice to see you and glad your doing well!
Honestly, I’ve been having pretty consistent results running Jack’s 5-12-26 w/ PureCal Calnit and weekly fulvic drenches. I guess i just want to get things dialed in even better. My environment/VPD is on point. The biggest thing that bugs me with Jack’s is that i feel my leaves always seem a bit dark. Also, my plants, while looking healthy inconsistently shoot out 7 and 9 blades leaves. I’d like to see them more consistently.
I still have a bit of 5-12-26 left, so i’m going to get some SOP, MKP and calcium acetate and play around with the N, P, K, Ca and Mg levels next run. Obviously not all at once, only making tiny changes, one ion at a time as @emdub27 suggested. That seems like great advice and gives me a solid starting point. Increasing calcium seems like the first logical tweak. Seems like that would put my calcium levels in a better spot and also correcting the Ca:Mg ratio.
I run DTW coco, in 1 gallon fabric pots and by mid flower I’m fertigating around 10 times a day to keep the media wet. I do notice the occasional salt build up but the weekly fulvic drenches keep that in check. I’m wondering if better ratios or even a change in humidity would help me there. My humidity is in the mid 40s during flower, ambient temps around 80F and LST around 77F (under LED lighting). I also start feeding a little bit lighter around week 6, in hopes to improve tastes. Anecdotally, I think this works but don’t know if this actually makes any difference.
These are the numbers i’ve been running with Jack’s at 3g, PureCal at 2.3g and Epsom at 0.5g per gallon. What I gleaned from the previous discussions in this forum is that my calcium seems low, right off the bat and my Ca:Mg ratio is off. It also looks like my PK levels are a bit low for flower.
Here’s the typical color of my leaves. They seem a bit dark to me and can take on a slight leathery feel. They really never look deficient though. So that’s a plus. ha
The only thing I might be concerned about with those numbers is the high K and Mg might antagonize the Ca. From what emdub has said the dark, leathery leaves are usually the results of high K.
I am also on a quest for better flavor. My last run was pretty spot on after emdub gave me some guidance. Buds are fat and tight with great smell but, after a nearly perfect dry and cure, they lack the flavor I was hoping for and the strain is known for great terps and flavor.
I wonder if my 2% brix has anything to do with it lol!
interesting. Here i thought K was on the low side of things and Ca could be increased. I thought N:K should be somewhere around 1:1.5 through 1:1.8 and that calcium should be a little higher than N
I’m always on a quest for better flavors and have tried things like flushing/not flushing and nothing seemed to make as much of a difference as genetics themself. I’ve been splitting the difference and just tapering my feed strength down a bit the last few weeks. Not sure if that’s helping me but anecdotally, I think it does but it’s hard to say. That said, I think things taste pretty good but like yourself, I’m always looking to improve. These days i’m a lightweight when it comes to smoke, so terps and taste are high on my list of desirables, potency is welcome but secondary. It doesn’t take much for me to get scrambled.
I did buy a brix refractometer and discovered my brix sucks balls! It’s only at a 2! I apparently also have a Ca deficiency at 201 ppm per gallon because it’s a hard division between the blue and white line! I guess what I’m trying to say is mixing salts is the easy part. Dialing it in to your particular set up and environment with out access to constant laboratory tissue analysis or pretty much what emdub said, is the hard part.