How to Take Brix Measurements

[Graytail]

I've been taking weekly brix readings from my flowering plants for a year now, so I decided to post a DIY for it.

Brix measurements can be tricky. You're measuring the percentage of "dissolved solids" in the sap of the plant, so if you test a crusty old leaf you'll get an artificially high reading. Less moisture=higher percentage of stuff in the fluid. Brix doesn't vary much across the plant, so it's not terribly important where the healthy leaf came from. It's more important to take the same sort of leaf from the same sort of place on every plant every time. I take a typical small 5-bladed leaf from mid-canopy. They're usually fairly plentiful - pretty crowded in there - lots to choose from.

Good brix readings for cannabis are 10-12.
Very good readings are in the 12-14 range.
Excellent readings are 14-16.
Spectacular readings can occasionally top 18.

If your results are especially high, be sure you're taking fair measurements.


Here's what I start with - vicegrips, a couple of thick metal slugs, a refractometer, and a typical healthy 5 bladed leaf.

I start by tucking the pertiole against the leaf and rolling/twisting it together.

Tuck it again, twist some more ...

I put the wad between the slugs and squish it carefully around the disks without releasing any juice ...

I reroll it, squish it for real and let a drop touch the prism ...

Flip it closed and take a reading ...

Reroll it, clean off the prism, and take another reading.

This is from a Carnival Cut I ran. I'll take a 17/17 any day.

 

[KingJohnC]

Very good guide!

 

[Radogast]

So the reading of the refractory meter is taken where the line of color ends?

 

[Graytail]

Yep, exactly.

 

[MassMedMan]

Looking to get one, tonight,,, is a beer wort one acceptable.. Like thirty bucks?? Thanks!!

 

[Icemud]

Very nice post graytail!!! I like the use of the vice grips and the slugs from an electrical box.

I wanted to share the video I made a while back which shows how I take my readings... pretty much same as Graytail...

I also created a thread back a few years ago for a place for people to document their readings... I haven't kept up with the thread as much as I wanted to back when I started it, but there still is some very good data there for different users to document and share readings and grow techniques/strains/details of the grow.

Here is the thread:
High Brix Refractometer Results Log & Data Thread - Post Your Brix Levels Here

And here is my video:

 

[Azimuth]

Old thread but super helpful info!

 

[CBDMed]

 

[KBUENOS]

So the reading of the refractory meter is taken where the line of color ends?

thank you for asking the question that I had.

 

[KBUENOS]

Yep, exactly.

Awesome, thank you so much, now to learn about brix, it is sugar right? no need to buy the brix product necessarily? asking for a friend I.. I mean uh. My friend uses botanicare, sweet raw, everything from the expert recipe this run, I really had great su. I mean my friend really had great success running only the basic recipe last time.

 

[Graytail]

Brix sugar isn't as simple as it sounds. The measurement is for solids in the plant fluid, which could mean petroleum, too. But we assume it isn't.

Don't dump molasses into the soil, and don't assume that "Brix" products are legit. Most of 'em aren't.

You want the roots feeding the soil biota with their sugary exudates, and causing the soil biota to use those sugars to break down minerals for the plant to feed on. Win win.

In this case we want to measure the health of the roots that are producing the sugar. When sugar is high, we know that the roots and the biota are happily in sync. (Unless we dumped fake crap into the soil).

The best way to set up the soil is to mineralize it first with a balanced mix including calcium. Search here for the term "mineralized", by Doc Bud or Gee64. Doc has a soil additive Kit and Gee has his own mix. They both know a great deal about soil and Brix and have the results to prove it.

 

[KBUENOS]

Brix sugar isn't as simple as it sounds. The measurement is for solids in the plant fluid, which could mean petroleum, too. But we assume it isn't.

Don't dump molasses into the soil, and don't assume that "Brix" products are legit. Most of 'em aren't.

You want the roots feeding the soil biota with their sugary exudates, and causing the soil biota to use those sugars to break down minerals for the plant to feed on. Win win.

In this case we want to measure the health of the roots that are producing the sugar. When sugar is high, we know that the roots and the biota are happily in sync. (Unless we dumped fake crap into the soil).

The best way to set up the soil is to mineralize it first with a balanced mix including calcium. Search here for the term "mineralized", by Doc Bud or Gee64. Doc has a soil additive Kit and Gee has his own mix. They both know a great deal about soil and Brix and have the results to prove it.

thank you so much for getting back to me, so fast. I will look these guys up, I fully agree with the sentiment on trusting companies lol it sounds silly talking about actually trusting a company, thats what I want to see more companies that are trust worthy, I honestly dont know anything about them, I do notice the play on words in their name, and advertisement, "Got Brix" for example, fortunately I do know what the word means so I dont fall for that alone do you mind if I follow your account? I really appreciate you talking with me here, if you would like to follow me, I will return the favor, and that goes for everyone who would like to follow my profile. I understand either way, I will wait until I know what your thoughts are on the subject.
Thank you again, so much, and I hope that you have an awesome day.
that goes for anyone, if you are having a bad time or just would like someone to talk to I would love the opportunity to get to know any of you, advantage of me please

 

[BeccaBuds]

I love the Vice-Grip pliers and conduit box knock-outs for a high-pressure squisher. MacGyvering at it's best!

 

[Waywardwayne]

I love the Vice-Grip pliers and conduit box knock-outs for a high-pressure squisher. MacGyvering at it's best!

A tiny couple welds and it’s a purposeful tool. Be sure to align it flat, just close them first.

 

[BeccaBuds]

A tiny couple welds and it’s a purposeful tool. Be sure to align it flat, just close them first.

I was thinking the same thing. Also envisioning brazing it in inert gas with induction heat. Woo hoo, my nerd side just got it's jollies!

 

[Azimuth]

Gee's been helping a few of us move down the higher brix path over in his Gee Spot Thread .

 

[Graytail]

The simplest way to grow high Brix is to get Doc Bud's Kit from the 'zon (if you can). We had a few dozen people here beta-testing it all through development. It works.

Reading Doc Bud's posts here would give a pretty complete education, starting with his earliest threads where he was still developing the right mix. That's when I got on board, back in 2013.

 

[Gee64]

Hey Graytail, I hope life finds you well.

This years soil mix, which is 1st run, is pulling solid 22's and likely higher if this darn low pressure system would ever leave. Summer is back for real in a couple days and flower is beginning, so this next week should be the peak brix readings for the year.

No foliars, just a good mix and some fish ferts. Prilled dolomite is proving to be the real key piece.

Here's my current mix

5 gal ewc
5 gal used soil
5 gal The Answer potting soil (bark and spaghnum)
5 gal perlite

3 cups prilled dolomite
1 cup blood meal
.5 cup bat guano
.5 cup glacial rock dust
3 cups feather meal
3 cups bone meal
1.5 cups greensand
.3 cups SRP
2 cups organic basmati rice
1 cup gypsum
3 cups kelp meal
2 cups alfalfa meal
1 cup oyster shell flour

Check out the fuzzy calcium line, this mix is The Bomb. I had 1 reading higher today at 22.5 but the cloudy days makes it hard to photograph the refractometer.

Here's one from last week.

This is last week and the same plant that is a 22 today, but likely higher as brix are just restoring now from a doozy of a storm. Yesterday this plant was only 16. It's a south african sativa from @Table Mountain Sativa Co , which is proving to be an outstanding pheno, so that definitely helps.

What you got growing these days?

 

[Waywardwayne]

Hi Gee64, amazing work here! I’m very much interested in following your recipe next summer but I don’t know what ewc is. My plants highest readings were 18 brix using store bought soil with added fish fertilizers and some compost. I was doing foliage spray as well with kelp and also milk. Next year I want to do it all home made and end up with high brix. And also go completely organic if possible.

 

[Gee64]

Hi Gee64, amazing work here! I’m very much interested in following your recipe next summer but I don’t know what ewc is. My plants highest readings were 18 brix using store bought soil with added fish fertilizers and some compost. I was doing foliage spray as well with kelp and also milk. Next year I want to do it all home made and end up with high brix. And also go completely organic if possible.

Fish ferts are a big part, they keep the myco fungii happy. EWC is Earth Worm Castings. Stop by The GeeSpot in my signature if you like, there's a bunch of organic nerds hanging out in there. We talk about all sorts of things. If you are pulling18 your doing excellent!