Doc Bud's High Brix Q&A With Pictures

How do I test? What do I need? Of course I'll do it
 
Thanks Major ...and i'l pass that on to all the fathers out there! Have a great day Dads....Cheers.....where's my java? :hmmmm:
 
36Gr0w said:
Question for everyone. Who is testing brix levels?
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I do all the time actually. I've just cut an OG Kush at sixteen Brix melting under the sun :laughtwo::tokin:

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Renmember to take various readings from different parts of the plant to understand how they change from branch to branch, and which is the right estimate :thumb:
 
I don't use foliars but I'm not a kit user :smokin2: :cheesygrinsmiley:
 
I'm not a kit user currently also. I make my own foliar sprays and haven't seen negatives, but I should start testing brix before and after to make sure it is effective, and to what extent. *Are brix testing kit users doing this?

*Edit* Do you have an average brix level?
 
Hey Doc!!

Been a while since I have been through... I have a question for ya...

So usually when I do test my brix levels, I usually test the sap at the cut I make on the stem, as well as the crushed leaf juice. To test the sap, immediately after I cut off the leaf sample, the stem forms a bubble of sap in which is what I spread onto my refractometer to test.... and with the leaf...ball it up, crush it a bunch, and then squeeze juice out with my pliers...

Now the question is this.. Usually the relationship to my sap to leaf is where the sap is a lower brix than the leaf....and this has been true every single time I have tested the plants...the sap is always lower....

Last night I tested my Ogiesel plant and the sap reading was 22 and the leaf crushed was a 16 brix..... which was the 1st reading where the sap was higher (much higher than the leaf).

Have you ever seen this? Any clue on what it could mean? I am going to check them again tonight when the lights come on at the same time to see if it was a error in data collection, but it was very interesting to say the least. Any thoughts on this?

***also, to add to this, the plants were given a compost tea about 2-3 hours previous to the readings being taken. The compost tea had very little sugars in it, other than about 20ml of carboload (5 sugars) for 5 gallons of water. I also gave the plants a foliar spray of the tea at the same time I fed the soil.

Common sense would tell me that the plant liked the compost tea feeding, ramped up production of sugars, and therefore the sap might be higher than the leaf which may have been previously producing less sugars the previous weeks? Other than that I don't know if there is a relation to sap vs crushed leaf juice, but I found it very interesting and wanted to hear your thoughts on it.
 
Hmm ... but the leaf is producing the sugars, so they would be traveling the other direction, no?

In my experience, when you get readings over 20 you should be suspicious. It'll be very interesting if you get similar readings again. :thumb:
 
Icemud said:
Hey Doc!!

Been a while since I have been through... I have a question for ya...

So usually when I do test my brix levels, I usually test the sap at the cut I make on the stem, as well as the crushed leaf juice. To test the sap, immediately after I cut off the leaf sample, the stem forms a bubble of sap in which is what I spread onto my refractometer to test.... and with the leaf...ball it up, crush it a bunch, and then squeeze juice out with my pliers...

Now the question is this.. Usually the relationship to my sap to leaf is where the sap is a lower brix than the leaf....and this has been true every single time I have tested the plants...the sap is always lower....

Last night I tested my Ogiesel plant and the sap reading was 22 and the leaf crushed was a 16 brix..... which was the 1st reading where the sap was higher (much higher than the leaf).

Have you ever seen this? Any clue on what it could mean? I am going to check them again tonight when the lights come on at the same time to see if it was a error in data collection, but it was very interesting to say the least. Any thoughts on this?

***also, to add to this, the plants were given a compost tea about 2-3 hours previous to the readings being taken. The compost tea had very little sugars in it, other than about 20ml of carboload (5 sugars) for 5 gallons of water. I also gave the plants a foliar spray of the tea at the same time I fed the soil.

Common sense would tell me that the plant liked the compost tea feeding, ramped up production of sugars, and therefore the sap might be higher than the leaf which may have been previously producing less sugars the previous weeks? Other than that I don't know if there is a relation to sap vs crushed leaf juice, but I found it very interesting and wanted to hear your thoughts on it.
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Graytail said:
Hmm ... but the leaf is producing the sugars, so they would be traveling the other direction, no?

In my experience, when you get readings over 20 you should be suspicious. It'll be very interesting if you get similar readings again. :thumb:
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So I repeated the test tonight. I tested at the exact same time last night, and took a sample from the same numbered node that I pulled the other sample from, also watered at exactly the same time, with the same mix of compost tea (which was about 2-3 hours before the test on both days).

Much to my surprise, the plants stem sap again was higher than the leaf reading, but the leaf reading did go up to around 19 brix, where yesterday it was only at 17 brix.

I calibrated the meter to check and make sure it was reading correctly with 0ppm r/o water.
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The plant is showing very good leaf posture which is always a good sign of high brix.
IMG_20150621_224817.jpg


The leaf itself, even though shows a past calcium deficiency has a very nice glossy shine to it so that is also a sign of high brix.
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Here is the test of the stem sap....
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Here is a test of the crushed leaf juice from the same sample. (very hard to read in the clear focused photo, but actually the line shows better in the blury photo....
IMG_20150621_224231.jpg
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Very interesting to say the least, but still not really sure why the sap is higher, where as in the past, the sap was always lower.

The only different thing I currently am doing is testing immediately days after the flip to 12/12, which in all other tests I am either in veg, or in later flowering.. IDK if this makes a difference though. (Does sugar production really ramp up that much in early stretch?

Since the leaf brix went up, maybe the high sap indicates the plant is getting healthier? IDK??

Another note to this.... the test was taken at 5 hours after the plants daytime started, which could also explain the high brix, since the plants highest rate of photosynthesis is right before the noon hour, when typically plant then gradually decrease the rate of photosynthesis for the remainder of the day.....
 
The big variations I've seen in my garden have been primarily due to leaf turgidity - how plump or dry they are. Dryer leaves will read a couple points higher. I've never done the sap test, and I think after reading about yours I'll probably give it a try. I haven't tested anything in weeks anyway and I should see what they have. :cheesygrinsmiley: The big advantage of your sap test is that no surface residue from foliars is involved. That variable has been bothering me lately, but a wash won't work because it would hydrate the leaf. But with your method, it's only the fluid.

Are you sure you're always getting enough fluid for a fair test? Not enough will get you a high reading ...
 
Graytail said:
The big variations I've seen in my garden have been primarily due to leaf turgidity - how plump or dry they are. Dryer leaves will read a couple points higher. I've never done the sap test, and I think after reading about yours I'll probably give it a try. I haven't tested anything in weeks anyway and I should see what they have. :cheesygrinsmiley: The big advantage of your sap test is that no surface residue from foliars is involved. That variable has been bothering me lately, but a wash won't work because it would hydrate the leaf. But with your method, it's only the fluid.

Are you sure you're always getting enough fluid for a fair test? Not enough will get you a high reading ...
Click to expand...

Yea the leaves are always usually pretty juicy and getting a reading from a good sized drop is usually not a problem from the stem or from the balled up clump of leaf material, I would say at least a pencil eraser diameter drop or larger after the lid is closed for almost all my tests.

I too always wondered how foliar sprays had effect from the residue which is why I started testing the sap directly too. I wanted to see if there is a pattern that I could easily see in the sap:leaf juice ratios but when looking at the many plants I've now tested at different parts of the grow, there doesn't see to be much of a pattern other than the sap is always lower than the leaf juice by at least 4-8 brix. That is why it caught me off guard when the sap actually registered higher than the leaf.

It's very interesting, and I wonder if the ratio between the 2 values/measurements has any value to what we are doing. Makes me also wonder what others are seeing as far as sap values vs leaf juice values. I will have to do more looking around to see if I can find any info on if there is any meaning to testing both, or if its unnecessary.

The leaf turgidity of these was very good, the leaves had great posture which I believe is a sign of good tugor pressure, and when I scrunched it, there definitely was a ton of juice that was able to be taken. The texture of the leaves is more thick and waxy with a little bit of stiffness to them, not really a dry stiffness, but more of a thick stiffness if that makes any sense.

Seeing the high readings isn't uncommon in my garden though as usually I see most of my plants at one point or another hit 16-20+, what throws me off really is the different ratios.... what it means and can we use the data somehow :)

Appreciate your knowledge and suggestions Graytail :) always a pleasure and appreciate your insight :)
 
Thank you, Icemud, for starting one of the more interesting discussions going on at the moment. This is intriguing, and I'll keep my ear tuned to the conversation as it develops. You guys are going to have me purchasing my own meter before you're done.
 
I posted I was not testing, but I think I will pick up a refractometer just for fun.
Since I have identical plants in HB soil and non-HB soil, it might make for an interesting comparison (cuttings are from the same plants).
I've wondered about the foliar residue too. I think I will do a quick wash and dry the leaves. It may lower the readings but I will only be comparing results with myself.
 
Been away at a famous event involving cannabis in the Bay Area......

Great discussion going on!
 
Thats why when I test its 3 days after a spray and/or feed. I think that's a good time because the plants had time to ingest some good food and the spray has had time to completely dry up. Im sure theres residue but its minimal at best. Maybe ill use a clean cloth to kinda dust off the leaves I pick next time...we'll see I reckon :)
 
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