Do we need to pH adjust our nutrient solutions?

[Emilya Green]

I have gained 3 things from this conversation.
First, I am glad that I have always used RO water with zero alkalinity issues.
Second, it is now confirmed in my mind that any buffered soil will eventually lose that buffering over time, and whether it be from positively or negatively charged nutrients, peat or minerals added by any means; soil wears out.
Third, I am more glad than ever that I went to TLO and don't have to worry about such things and no longer have to worry that my grows are being affected by CYA soil company executives who couldn't give a straight answer if their lives depended on it.

 

[FelipeBlu]

Also from the same source (Thanks Farside - Excellent read!):

“The best guide when selecting an appropriate water-soluble fertilizer is to balance the proportion of nitrogen in the ammoniacal form (acid) against the irrigation water alkalinity (base).

Although other factors affect substrate-pH, research has shown that it is the balance between the ammoniacal nitrogen in the fertilizer and water alkalinity that has the greatest effect on substrate-pH on long-term crops.”

There is a table included in the article that presents appropriate ratios of the different nitrogen types that will balance various levels of irrigation water alkalinity.

Good stuff!

 

[Homer Simpson]

I have gained 3 things from this conversation.
First, I am glad that I have always used RO water with zero alkalinity issues.
Second, it is now confirmed in my mind that any buffered soil will eventually lose that buffering over time, and whether it be from positively or negatively charged nutrients, peat or minerals added by any means; soil wears out.
Third, I am more glad than ever that I went to TLO and don't have to worry about such things and no longer have to worry that my grows are being affected by CYA soil company executives who couldn't give a straight answer if their lives depended on it.

I think just about everybody has read and uses your watering system Emilya so I think most of us look at you as a real expert out here so I am really curious about your opinion regarding organics and TLO regarding bugs. I am doing my first grow in 20 years but those many years ago when I grew my biggest problem was with spider mites.

It just seems to me the chance of getting spider mites and other pests would be exponentially larger using a soil that has been composted and has true living organisms? That is what has been stopping me from considering the natural route because I figure things like coco have nothing living in them thereby lessening the chance of getting bugs. What is the flaw in my thinking?

 

[Emilya Green]

I think just about everybody has read and uses your watering system Emilya so I think most of us look at you as a real expert out here so I am really curious about your opinion regarding organics and TLO regarding bugs. I am doing my first grow in 20 years but those many years ago when I grew my biggest problem was with spider mites.

It just seems to me the chance of getting spider mites and other pests would be exponentially larger using a soil that has been composted and has true living organisms? That is what has been stopping me from considering the natural route because I figure things like coco have nothing living in them thereby lessening the chance of getting bugs. What is the flaw in my thinking?

Thanks for the kind words Homer, much appreciated.
Mites don't just appear out of thin air and automatically become part of your grow because your soil is living. They could not exist in the environment of a hot compost pile with at best decomposing plant matter. I do have a few bugs that live in my soil, earthworms, nematodes and things like that, and I celebrate when I see that my soil is this compatable to larger life such as this, and one of the reasons that I use mulch in my containers... to keep this stuff alive.
Predatory bugs do not grow out of a composting soil... they exist within their own life cycles, among living plants. If you break that cycle or don't allow it to intersect with your grow, you will be ok.
One common route in to your space for some bugs is via store bought soil. If you suspect your source or feel inclined to buy mass marketed soil, you should sterilize it when it hits your door. Your chance of getting bugs goes up 50% every time you bring a plant in from outside of your controlled area. If you set a plant outdoors from time to time out next to a vegetable garden, you are inviting bugs to investigate it. Chances are good that you will bring them in with the plants if you return them to the inside. If you bring in clones from another grow, same thing. In a closed and clean environment however, there is little chance that mites could invade... unless you somehow bring them in on your clothing, your pets, etc.

 

[nobodyhere]

I'd make it easier and just run two clones. One pH adjusted and one at wherever it lands after mixing. Wish I had the room for science.

my guess: the ph adjusted looks better and yields more than the one that is never ph'ed.

 

[NOOOBIENOT]

Wow after all this reading about soil I sure am glad I use coco and don't miss it(soil) , I just want good tasting decent yielding plants with out all the frickin stress I am reading here .

 

[FelipeBlu]

Also from Farside’s source, how to test your substrate pH and EC using the Pour-thru method:

Step 1. Irrigate the plant one hour before testing, making sure the substrate is thoroughly wet. Allow the pots to drain for 30-60 minutes.

Step 2. Once drainage has stopped, place the pot to be sampled into a plastic saucer and pour onto the surface enough distilled water to get about 2 oz. (50 ml) to come out of the bottom of the pot.

Step 3. Measure pH and EC directly in the leachate.

 

[Homer Simpson]

Thanks for the kind words Homer, much appreciated.
Mites don't just appear out of thin air and automatically become part of your grow because your soil is living. They could not exist in the environment of a hot compost pile with at best decomposing plant matter. I do have a few bugs that live in my soil, earthworms, nematodes and things like that, and I celebrate when I see that my soil is this compatable to larger life such as this, and one of the reasons that I use mulch in my containers... to keep this stuff alive.
Predatory bugs do not grow out of a composting soil... they exist within their own life cycles, among living plants. If you break that cycle or don't allow it to intersect with your grow, you will be ok.
One common route in to your space for some bugs is via store bought soil. If you suspect your source or feel inclined to buy mass marketed soil, you should sterilize it when it hits your door. Your chance of getting bugs goes up 50% every time you bring a plant in from outside of your controlled area. If you set a plant outdoors from time to time out next to a vegetable garden, you are inviting bugs to investigate it. Chances are good that you will bring them in with the plants if you return them to the inside. If you bring in clones from another grow, same thing. In a closed and clean environment however, there is little chance that mites could invade... unless you somehow bring them in on your clothing, your pets, etc.

Thank you for taking the time to write such a comprehensive reply Emilya. My first recent grow is still not complete so my learning curve has been pretty steep so I don't see going organic in the near future but with you alleviating my bug concern I think the likelihood of going that way someday is more likely with all the benefits I have read of. Thanks again.

 

[Homer Simpson]

my guess: the ph adjusted looks better and yields more than the one that is never ph'ed.

That really is the $64 question? From what the expert Shed was talking to says you think it wouldn't but I found this quote on this page about, "Understanding Plant Nutrition: Irrigation Water Alkalinity & pH". Understanding Plant Nutrition: Irrigation Water Alkalinity & pH

"Don’t ignore water pH, though. Water pH is still important for crop management because it affects the solubility of fertilizers and the efficacy of insecticides and fungicides before you apply it to the crop (Figure 2). Generally, the higher the water pH, the lower the solubility of these materials."

I have room for science but unfortunately in my area only four plants are legal so it’s kind of hard to do a lot of tests and have my regular plants and stay under the limit.

 

[Emilya Green]

I have room for science but unfortunately in my area only four plants are legal so it’s kind of hard to do a lot of tests and have my regular plants and stay under the limit.

They should allow for a few more plants just for science... "I swear, I will not smoke this plant... unless of course it is for science."

 

[InTheShed]

I am more glad than ever that I went to TLO and don't have to worry about such things

Not sure what TLO is Emilya. I'm probably not alone in that either. Can you give a brief explanation?

Although other factors affect substrate-pH, research has shown that it is the balance between the ammoniacal nitrogen in the fertilizer and water alkalinity that has the greatest effect on substrate-pH on long-term crops.”

Thanks Felipe! Confirmation keeps coming .

my guess: the ph adjusted looks better and yields more than the one that is never ph'ed.

Your guess is as good as yours!

Wow after all this reading about soil I sure am glad I use coco and don't miss it(soil) , I just want good tasting decent yielding plants with out all the frickin stress I am reading here .

Glad I could help NOOBIE! You of course will need to continue to pH your nutes with every watering. I no longer need to. I only need to check the pH of my substrate every so often.

Also from Farside’s source, how to test your substrate pH and EC using the Pour-thru method:
Step 1. Irrigate the plant one hour before testing, making sure the substrate is thoroughly wet. Allow the pots to drain for 30-60 minutes.
Step 2. Once drainage has stopped, place the pot to be sampled into a plastic saucer and pour onto the surface enough distilled water to get about 2 oz. (50 ml) to come out of the bottom of the pot.
Step 3. Measure pH and EC directly in the leachate.
For more information on the Pour-thru method, see the web site www.pourthruinfo.com.

That was similar to one of my pH check methods, but I find slurry testing to be easier and it doesn't flush the plant with distilled water.

 

[Emilya Green]

Not sure what TLO is Emilya. I'm probably not alone in that either. Can you give a brief explanation?

I can.
True Living Organic

 

[InTheShed]

Brief, nice!

 

[FelipeBlu]

That was similar to one of my pH check methods, but I find slurry testing to be easier and it doesn't flush the plant with distilled water.

From where in the pot do you take your sample for the slurry test?

And only 2 oz (50ml) of leachate is produced. That’s not exactly flushing.

 

[InTheShed]

Not exactly, no. But the pour through method seems very inexact to me. If I pour enough nutes into the pot to completely soak it it might drip for an hour! Slurry method seems simpler and faster. I usually dig down a few inches for the material.

 

[SmokeLake]

Im growing in ProMix HP CC I have been using ph up to get my nutes ph going in up to 5.8-5.9 ever since i started doing so ive had no issues and healthy plants. Without ph up im at 5.2-5.3 if i recall. My water is city water left sitting 48hrs on avg. I will be seeking a water analysis and based on the info in this thread im going to investigate farther ill post my results. Based on my farming background it is true as someone said proper soil mix with right balance of nutes or fertilizer is key as Mother Nature doest ph the rain that falls. Great thread i love understanding why and how things work not just because they work!!

 

[FelipeBlu]

I usually dig down a few inches for the material.

In one location, or in several?

This introduces uncertainty in me as to the representative nature of the sample to the entire medium. Whereas the pour-thru provides a sample of the entire medium.

 

[InTheShed]

In the real world everything introduces uncertainty. The pour through method is relying on a number of assumptions as well. Where that 2 ounces of water drips from for one. What soaking a plant to drainage means is another. Take your pick of uncertainties!

 

[farside05]

Not exactly, no. But the pour through method seems very inexact to me. If I pour enough nutes into the pot to completely soak it it might drip for an hour! Slurry method seems simpler and faster. I usually dig down a few inches for the material.

The Substrate article gives instructions for 4 different methods. Choose your preference. It does suggest that whichever way you decide, stick with it for consistency.

 

[InTheShed]

Good advice farside!