Originally Posted by Nondual

I can see for indoor growers with smaller plants doing this type of testing is probably not worthwhile. For large outdoor growers I think it's valuable. These guys are pushing things trying to maximize yields and monitoring plant health is important for disease/pest issues and still believe it helps quality. You are assuring your plants are performing at their peak. The top outdoor growers I know test their soil.

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Yeah for larger scale OD I can see where this would have more value, but for the guy running a small indoor op not so much.

Like when the scale of the operation is large enough where the grower might not have such a personal relationship with each plant or where taking off a good sized clip from a large OD plant not such a big deal but if I was to take off a few fans or a snip of a branch every week from my small IND plants there would be nothing left by harvest.

Not discounting the method just the use of a refractometer in all cases.

Originally Posted by rrog

We know that starting with great soil, amending properly as we go, produces the best product. Not sure I need a meter to measure brix to confirm this.

I know the value of soil, tissue and sap testing in large scale agriculture. It helps growers refine programs. It's these growers that outperform others in yield, controlling losses and crop quality. Brix is only part of the equation. Jeez you could add different teas and see how the plant actually responds.

I'm just saying how do you know it's the best product until you do some testing? You're still relying on your senses which are subjective. If testing of this type has proven it's value in open agriculture why won't it provide at least some value in growing MJ? That's what I don't get.

It's not that I don't get where some of you are coming from and in general agree. I'm just more of a science guy. That's part of what I do in the 'real' world and know the value.

[rrog]

I'm a formally trained science guy and love to measure. Just not seeing the need in my case with a small personal grow.

[EclipseFour20]

Originally Posted by ShroomDr

...Its hard to get a 'full drop' of MJ fluid. I could probably do it if i hacked a large enough piece off, but a large fan leave will (generally) not suffice.

I even bought a garlic press to fold the leaf up in, and juice, its just not worth the trouble.

IMO...the garlic press is great for veggies like carrots and beans, but for getting sap from leaves....these guys did it right by modifying vise grips with some stainless steel caps.

https://www.pikeagri.com/vmchk/Sap-Sa...uct-flyer.html


But for $27 bucks plus shipping...I might do one myself. Until then, here is how I get 2-5 nice sized drops from 4-5 fan leaves. Kinda ghetto, but easy.

1. Cut 4-5 healthy fan leaves from the top 1/3 of the plant--retaining as much of the stem as possible.
2. Using a folded clear plastic sheet, (mine was salvaged from a clear report cover and cut to 3" x 5" and folded longways so it is 1.5" x 5") position the leaves so about 1/8" of the stem extends past the edge of the plastic. So...you have a sandwich, plastic + leaf + plastic...with the leaf section nearest the fold and all stem ends aligned...pinched together with your thumb and index finger.
3. Squeeze the sap from the leaves (I use a round tool and slowly roll it towards the stem ends as the plastic strip is resting on the table edge...similar to the action of a rolling pin) and as the sap accumulates I dab the stem ends on the refractometer.

If you squeeze/pinch the leaf stem with your fingers...you might get something--but for sure, you will have to sore fingers...and shredded leaves and stems.

That's how I do it and it works for me!

[EclipseFour20]

An example for why you would to test a plant's brix in a small garden. Foliar Spray; to verify that it is effective. If the brix increases after you spray, then it is good for the plant...but if one observes a decrease in brix--then the spray probably is doing more harm than good.

[rrog]

Assuming you feel there's value in feeding a plant through its leaves. Another debate entirely

[EclipseFour20]

Originally Posted by rrog

Assuming you feel there's value in feeding a plant through its leaves. Another debate entirely

Amen brutha! Interesting pamphlet on foliar feeding that I found very valuable. https://www.midwestlabs.com/images/s..._nutrition.pdf

One nugget that I gleaned is--adding a bit of nitrogen to all foliar sprays increases the plant uptake of the spray's active ingredients; makes sense as most herbicides include urea to speed up the process of plant uptake.

The second golden nugget is the discussion identifying which nutrients are "best" when foliar sprayed...as opposed to root fed.

But like our buddy rrog said...that is a another debate entirely!

[ShroomDr]

Im gonna order these and report back.


Irwin 23EL5 Vise Grip 8-Inch Locking Sheet Metal Tool


https://www.amazon.com/Irwin-23EL5-8-...dp/B0000TFGFU/

$21.75 out the door


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Listen to the link analogue posted, it is excellent.

You want to grow the healthiest plant possible is why you would use it. And here is the thing...the fastest way to lower the brix of any plant, including this one, is to overload it on nitrates. By measuring brix you can push a plant without overdoing it. It is a misconception that more nutes means higher brix just cause you are measuring solids...push a plant too far and it gets sick like a fat kid on wheat, sugar and vegetable oil.

Then you add sap pH testing on top of that and figure out how to maintain that pH at 6.4 and you ain't gotta worry about fungus or insect attack no mo...period.

If that isn't valuable to mj growing I don't know what is.

I will bet you this...most of the dwc users are going to have low brix...or lower at least cause those systems allow the user to force feed nitrate. Once they do that an endless cycle of pesticides, fungicides, shit to fight root aphids is set in motion.

Personally I can run around 11-12 in coco and up to 14 in peat. it is a fine line between enough and too much, especially nitrate nitrogen.

I use vice grips to squeeze the sap outta leaves. It should be no harder with mj than any other plant...if there ain't no sap you can bet your brix is kinda on the low side.

[OrganicBuds]

Originally Posted by rrog

I'm a formally trained science guy and love to measure. Just not seeing the need in my case with a small personal grow.

You are right, small grows have no need for brix measurements. This is for outdoor growing, where you have 8 month old plants that need dialing in.

I equate measuring brix to hydro guys checking the run off water. In a lab, one would give the plants water at a certain PPM, ph, and nute levels. After feeding you would then test the run off and see what the plant used up and how it effected the run off.

Kind of the same thing with brix. If you test your plant everyday at 12 noon, and get a brix reading of 13, then that is your base. Then lets say you make a home made Tea from ingredients that you have never used before or at altered amounts. Water the plants with the tea at dawn, and by 12 noon take another sample. If your brix reading has crashed, then your tea was no good. If your brix goes up, keep that recipe.