@Fitzera @shag or anyone else.
Curious as to (specifically) what kind of calcium amendments do you use for soil and for top dress. Also what do you use to increase Boron in the soil? I’d think you’d have to be very careful with not adding too much. How do you dial it in just right?
Seems like trail/error with spectrum analysis would be needed to really know for sure. If so, can you recommend any budget friendly labs that would do this type of service?
I use solution grade gypsum myself.
Plain old Boric acid is the cheapest way to go.
This is not just a simple answer sorry.
You will need to play around with things to find what your particular needs are.
As @ReikoX stated he has been working toward this for a while now and is still working things out, it is a long and winding road with many factors involved.
I have studied under slownickle for many years and I still have not perfected the use of calcium and boron ect.
He is the expert on this, I am not.
But
The end goal is to achieve nearly 100% calcium saturation in the soil whenever you are able to anyway.
Leaf tissue testing, as well as soil analysis along with real-time nutrient monitoring, is all probably needed, I have not done any of this myself.
For sure, this is no doubt the best way but can be costly for someone on a fixed income like I am.
I can not recommend any lab myself, I do not send in samples.
Maybe @ReikoX can, I think has sent in samples himself, but don’t really know.
I usually just top dress with gypsum and bump up the boron a bit when I do.
The proper way would be test the soil and amend it according to those findings.
I kinda wing it, but I try to read my plants as they will usually tell me if I make a mistake.
But by the time you see them react it may be a bit late in the game so this is not the best method.
I grow in a 4x4 tent and only grow for myself, so it is not like I have big money on the line, and I worry less than those who have more to lose.
I was able to rid myself of hollow stems just by top-dressing gypsum and adding a bit of extra Boron.
More calcium usually requires more Boron…Usually.
Also, I have been trying to push more calcium and recently I have been seeing what I think is a Phosphorus deficiency.
So I will be working on that in the future.
I also feel when you increase calcium you need to increase boron as well as “P”.
How to do this in the best possible way and how much to use and when is still to be determined.
As I said in a previous post, I feel those doing the crop steering with all the monitoring devices would be the folks to tell us what they see on the monitors and that could help us find the proper answers you seek.
Me, I am just kinda guessing at the amounts and the timing of such amendments.
While it seems to be going OK for me it is not the best method.
So proper testing along with real time root zone monitoring is the real answer you seek.
But that can become costly for the little guy and may not be realistic for most.
I know that is not exactly the answer you had hoped for, but I hope that will get you pointed in the right direction anyway.
Good luck with the adventure.
Shag
Bro…I don’t know of you’re joking or not…is this real.!!!
Yes, my BOG LSD was the only strain out of 5 that grew hollow stems during my last grow too. Everything else was solid and woody.
My guess is these types are genetically predisposed to being calcium hogs.
Calcium hogs tend to be better than average plants.
This may explain why folks seem to love plants with hollow stems.
For calcium specific inputs I use Oyster shell(cal carb), calcium bentonite(de), Gypsum and Dolomite. I only top dress with the Gypsum and de.
Worm castings and organic matter are supposed to be good for boron, i dont add a specific boron amendment.
A soil test would be nice but this is my own small personal garden, not overly concerned.
Well shit…now I feel like I didn’t get the full potential of the plant. Next time. 
Thanks for the tip(s) shaggy and everyone…good thread.
So in conclusion hollow stems mean the pants need calcium?
I am using cal mag in all my plants on leds and they all have hollow stems, now I think I might change a little thing to have better results.
I do a soil test after each round and use that to calculate what to add for the next grow. I use Logan Labs, but Slownickel prefers Spectrum. I get the complete test with AA@8.2 and a saturated paste test. Comes out to about $100.
If you want to head down this rabbit hole, check out Steve Solomon’s book The Intelligent Gardener. That’s a good place to get your feet wet.
@ReikoX
Thanks for that, it is good info.
I still need to look into that book, I am getting back to growing veggies now too.
Seems like a good read 
In my opinion, yes, and Gypsum is the fix, pretty dam simple science.
Might I politely suggest you do not get more Cal/Mag mixed in one bottle?
This product was made to fill a void in bottled fertilizer sold in hydro stores.
You should be adding calcium when you need calcium and Mag when you need mag.
Too much Mag can increase compaction in the soil and can cause other issues too.
I choose to keep mag low in the soil when possible.
Also if we need to crank Calcium as much as possible and we always do…
Then, if you add cal/mag to get there, that can mess things up but good.
I like to spray Mag nitrate on my plants, when I can or see the need.
I prefer amino-chelated products for Calcium and Magnesium but I mostly use Gypsum for ease of use and it is fairly cheap when compared with a good amino acid chelated product.
Please report back to us with your results.
I would love to hear if this works for you or even if it does not.
Just remember if you crank the Calcium you will probably need to increase Boron, but usually not above 3ppm especially for those who don’t have a good handle on things.
I am also finding with high powered LED’s you need to increase “P” without increasing “K” too much.
So that has to be factored into the equation.
I also believe this is the reason some folks don’t like growing with LED’s.
It would seem, to me anyway…that LED’s can change the way the plant feeds.
Got it, but you didn’t, my bad.
I use calmag because my plants need it while under led, my other growing section with hps don’t require any cal mag and they remain happy.
Cal mag cannot correct such a gap that make holow stems.
So yeah, right now I have 3 Northen lights almost ready, 1 to 2 weeks to harvest and I will post how stems are by harvesting time.
Once I pot up my criticals in a few weeks the first water will have some gypsum like half a spoon per pot, its a bit over 1 gal pots.
And then I will report back.
I like hollow stems but I would like to improve yelds, but if by increasing gypsum I will have aboron deficiency I might want to keep it without gypsum.
Live and try, try and learn.
Oh I have to do it by spoon because I don’t have a meter for ppm.
Ok, good to see you get it about the Cal/mag. 
You really should not with a quick top dress now and then, but it could happen if you are already low on Boron to begin with.
It is hard to know what is going on in someone else’s room. 
For reference, most food will/should come in at or about 1 ppm boron.
@ReikoX was cranking calcium pretty good and was only feeding 3 ppm boron.
So you can probably double what you are doing before you start getting on the low side of boron.
Man, I appreciate all but I am kind of starting, so I keep things very basic, indeed I notice tje hollow stems but really toight it was normal or a strain trace, and hollow stem makes them dry better and faster.
Thos to say that I even don’t know what boron is or how to mix it with the water.
I can enrich the soil with calcium, I will need to check on boron.
You see I am the kind of guy that don’t want to have 25 flasks with powder of all nuclear nutrients, I ise biobizz all mix and I spend half tje dose of the biobizz nutrients shedule, then I remove the roots and add some compost and re use the soil, maybe the compost isn’t sharp or is just unballanced.
I know our gold is to get the best of it so the usual “its a weed it will grow in the wild without any spetial treatment” isn’t a excuse so I am going to check on boron and meanwhile will get a bag of gypsum so I can try and check the hollow stems thing see if I can manage to have some solid ones and check the end result.
@DougDawson I have to agree with you. A mutation regarding the ability to uptake certain minerals are not THAT uncommon. So every problem with hollow stems can’t be solved with adding more gypsum. But I would bet that a great majority of cases is of the deficit nature.
Pz 
I also read that. On the MrNice forums, on male selection thread, Shantibaba says that that was one of the things he looks for… (between other things).
Citation:“Males that have large hollow main stems are sought out rather than males that are more pith-filled stems - the main reason are that large hollow stemmed males are better THC producers than other plants.”
HG!
Man, what a fascinating thread! Never expected the conversation to get soo deep - I love it!
So i’ve read that Kelp would be a good organic way to add boron. Are there any other organic ways you guys add boron to living soil?
I wouldn’t worry about boron. I don’t think it’s ever deficient without another deficiency being responsible…
Boy, I wouldn’t worry. Gypsum is an old tried and true ingredient for tasty pot. I’ve used a whole bag in a 5 by 10 outdoor plot. The powdered gypsum coats heavy clay soil clumps so it doesn’t stick together. Like rolling sticky dough in flour kinda. It also makes weed tasty used( topdress) a couple weeks before harvest.
I never had an issue in all sorts of soil. The calcium is a bonus.
Main thing is, gypsum raises soil ph, so you need to go easy or time its use.
Thank you for your tip, less doubts on it with yoir input, will definitely use some.
