Advancing Eco Agriculture, Product Science

[plantingplants]

Question for all the ec probe users: How do you factor soil moisture level into your readings? And in general, how do you factor moisture in with manipulating EC? For ex if your EC is low, you might be tempted to raise it by fertilizing, but if you just let it dry out a little then EC will raise...

 

[slownickel]

And since you know these things riddle me this. All anions compete yea? And P is the hardest to take up of the anions, yea? Then doesn't the sulfate in gypsum block the uptake of phosphate?

I have not figured out how to work around that yet. Have you?

Having a hard time with P?

Hint... it is translocatable.

From the latest leaf sample results, where we had the highest P we also had the highest S and..... we had over 2000 ppm of S in the soil.

Without getting your Ca right, you are never going to get the P uptake you are after.

And as you are seeing, K is the enemy in trying to achieve both those objectives.

 

[slownickel]

Question for all the ec probe users: How do you factor soil moisture level into your readings? And in general, how do you factor moisture in with manipulating EC? For ex if your EC is low, you might be tempted to raise it by fertilizing, but if you just let it dry out a little then EC will raise...

EC meters are a bit dangerous if used incorrectly. Always test your conductivity at near field capacity (recently well watered).

Testing when it is dry will generate bad data.

We just back EC data of 2.6 and the plants are doing great! 130ppm of nitrates and still cranking.... why? Guess!!! Hi Calcium!

High Ca, high P and keeping the sum of K and Na below 10...

Even so, what the grower needs now prior to hitting full stride flip? Start the cycle over! High Ca, get that K down. Get that N down. Flush and gypsum!!

 

[jidoka]

Having a hard time with P?

Hint... it is translocatable.

From the latest leaf sample results, where we had the highest P we also had the highest S and..... we had over 2000 ppm of S in the soil.

Without getting your Ca right, you are never going to get the P uptake you are after.

And as you are seeing, K is the enemy in trying to achieve both those objectives.

I actually agree with you. And yea...I have not completely figured out P yet. Thank you for the explanation.

I have been moving to K less than 2% and then spray about 4 weeks into flower. Still not happy completely with P

 

[plantingplants]

Ok. Figured youd have to keep the water variable constant.

Ec of 2.6 measured with what? Lab (SME)? That's only ~1.6 EC with a probe.

Makes me want to put onsome more calnit .

 

[slownickel]

Ok. Figured youd have to keep the water variable constant.

Ec of 2.6 measured with what? Lab (SME)? That's only ~1.6 EC with a probe.

Makes me want to put onsome more calnit .

Lab number.... the aminos are what is driving the EC.... they add up quick.

 

[GreenHands13]

I'm not convinced that P is a problem if it is in the soil in good relative numbers. I have a large experiment going on right now. Probably not the smartest thing to do but I feel confident in it. The only P source this run has gotten is what is in pacific grow and the very small amount in the kelp I'm using.

 

[EasyGoing]

Question for all the ec probe users: How do you factor soil moisture level into your readings? And in general, how do you factor moisture in with manipulating EC? For ex if your EC is low, you might be tempted to raise it by fertilizing, but if you just let it dry out a little then EC will raise...

I have been taking my EC measurements at the same time after a watering for the exact reasons you state. I find the opposite in my readings. When the soil is wet, it reads the highest ec. If I wait for the soil to dry out my reading become low.

I tend to water in the AM's if possible, and I take my reading the next day 24 hours after a watering. Seems to stay pretty consistent for me.

 

[EasyGoing]

I meant high sap nitrate and/or K attracts bugs. And that forces the grower to use insecticides

I see.

ANd yes, I may have excesses. That is the reason I came on asking about the ppms in the soil. I am far from perfect, and far from understanding why I am going wrong. That is why I come on the boards.

As for why an IPM........ I live next to a river bank that is filled with blackberry bushes that are infested with two spotted mites and russets........ I don't give a shit how healthy your plants are, those bugs don't mess around. The river is on the next property, but only yards away. So I can't treat that area without possibly pissing my neighbor off. Plant sap dips and I am infested. IPM is a must, IMO, in my situation.

 

[jidoka]

[URL=https://www.icmag.com/ic/picture.php?albumid=72272&pictureid=1762776&thumb=1]View Image[/url] I'm not convinced that P is a problem if it is in the soil in good relative numbers. I have a large experiment going on right now. Probably not the smartest thing to do but I feel confident in it. The only P source this run has gotten is what is in pacific grow and the very small amount in the kelp I'm using.

Nice grow.

Do you see much of an EC bump from pacific grow. I don't. My theory is the high organic matter allows it to stay in amino vs ionic form.

I have always ran lower P. My experiment is with higher this yr

 

[slownickel]

[URL=https://www.icmag.com/ic/picture.php?albumid=72272&pictureid=1762776&thumb=1]View Image[/url] I'm not convinced that P is a problem if it is in the soil in good relative numbers. I have a large experiment going on right now. Probably not the smartest thing to do but I feel confident in it. The only P source this run has gotten is what is in pacific grow and the very small amount in the kelp I'm using.

Can't wait to hear this one!!

 

[GreenHands13]

Nice grow.

Do you see much of an EC bump from pacific grow. I don't. My theory is the high organic matter allows it to stay in amino vs ionic form.

I have always ran lower P. My experiment is with higher this yr

It definitley bumps the EC of my feed, but ya I agree i don't see it change my soil EC a lot. With these high carbon soils I definitley think a lot fixates.

 

[jidoka]

Yea...somebody told me big pumpkin soil is extremely high carbon with tcecs of up to 90. I have been screwing around trying to build one of those. It is almost impossible to move the soil EC on the meter with fertigation. And EC stays in the 0.3-0,4 range...seemingly very mellow. It becomes totally about the microbes.

If I ever get it figured out I wanna see if I can grow in maybe 20 gal pots in a gh without a bunch of inputs all the time

 

[EasyGoing]

I know a guy that grows competition pumpkins out of Half Moon Bay. They use a lot of manure. I think his biggest pumpkin was around a ton. Still have some of his seeds he gave me from his top ten placement pumpkin.

Maybe if I get my dispensary, and I can move away from only farming, I might start up some pumpkins for fun. Love me some pumpkin seeds toasted and salted.

 

[EasyGoing]

It definitley bumps the EC of my feed, but ya I agree i don't see it change my soil EC a lot. With these high carbon soils I definitley think a lot fixates.

What ec's are you running?

I was doing testing last year, and even at the rate of 12ml per gallon at an 8% soil volume, the pacific grow didn't move my ppms AT ALL. Didn't start to move until top dressings or aminos.

 

[plantingplants]

Bottom, top
4100, 1800 no3
200, 58 ca
1900, 520 k
7.1, 6.5 ph

The bottom leaves I tested were in varying states of yellow. The sap was brownish. How is it yellow with that much no3? Also it's not yellow at the top even with the K difference.. And this is coots based soil and has/had a lot of K. Bout to send in a sample.

 

[plantingplants]

Easy why would your ec raise from applying a 2% N product at such low doses? That's something like top dressing a half pound of manure...

 

[jidoka]

You have more than 3x as much K as your plant wants. That a) explains the high pH in the lower leaf and b) guarantees you do not have enough Ca and/or Mg in the plant.

The lack of Mg along with the excess no3 guarantees you do not have enough phosphate

Excess no3 does not mean enough protein. Protein (chlorophyll) takes Mg also

Problem 1 is too much K. You gotta get enough gypsum and water in that soil to flush the K. Then get Mg and P in the plant...spray them to avoid the soil problems. Try Mg first

 

[plantingplants]

Dang alright lets see where this goes. There are two other yellowing plants in the same pot. Same variety but maybe diff phenos. I will get sap data on them as well to see if we got the same issue. If so I could try two different sprays and have one control. Or maybe keep two controls.

Ill also test another pot with same soil.

Are you removing the thick ribs on big fan leaves that connect to the petiole? I have been pinching off the back end there until the leaflets separate, to keep it consistent. The petiole and its fingers are juicy and tempting to squeeze but idk if it would change the reading?

 

[redlaser]

Bottom, top
4100, 1800 no3
200, 58 ca
1900, 520 k
7.1, 6.5 ph

The bottom leaves I tested were in varying states of yellow. The sap was brownish. How is it yellow with that much no3? Also it's not yellow at the top even with the K difference.. And this is coots based soil and has/had a lot of K. Bout to send in a sample.

Does that coots based soil contain any neem? Neem is anti fungal and affects nematode populations as well.
Not sure about its affects on bacteria but if used probably is not helping