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Do we need to pH adjust our nutrient solutions?

nobodyhere

Well-Known Member
Okay, after reading the five articles, and sitting and thinking, I have a question. So we know as indoor growers, especially under LED lights (for some reason), that a lot of calcium and magnesium are typically needed from early flowering/stretch until harvest.

From the articles, the suggested levels of Ca and Mg are 63 ppm and 21 ppm for orchids and most other flowering/fruiting plants. Together, when provided in low-EC RO water, this concentration is within the range of moderate alkalinity, which would suggest a fertilizer with about 25% ammoniacal N.

But if a grower finds that more CalMag is required, and the combined concentration of Ca and Mg, contributed by the CalMag and other nutes, now puts the feeding solution into high alkalinity. A fertilizer with about 40% ammoniacal N is now recommended, in order to balance the higher alkalinity.

Am I reading this right? I have looked at a lot of the popular water-soluble fertilizers, and not many have that much ammoniacal N (Dyna-Gro Grow has ~40%, and Fox Farm Grow Big has ~50%). Even the MSU RO formula (from the articles), only provides ~6% ammoniacal N.
This is why, even with soil with a ton of N added, and giving copious amounts of N in organic ferts throughout veg and bloom, I still hit most plants with a few doses of grow big first couple weeks into bloom. I don't use a ton of it, but it's there.
 

Amy Gardner

Member of the Month: March 2018 - Photo of the Month: April, Dec 2018, Apr 2019
Seeing as the topic of electrical charge in soil came up during this thread, Graytail just posted this vvv in response to a conversation about the occasional eclectic shock that’s been known to happen on contact with some of the DBHBB drenches and it contains a great link to article about conductivity in soil.

A large part of the nutriment regimen for High Brix is based on the electrical charge of the soil. There are all sort of ions and cations being created all the time, from the splitting of mineral molecules by the biota. The drenches flood the soil with formulas that are designed to electrically split existing mineral molecules, or to set up a charge that assists the biota. There is a soil measure called ERG (Energy Released per Gram) - literally measuring the electrical charge in the soil.

Electrical Conductivity: The Pulse of the Soil | EcoFarming Daily


So, the DBHBB drenches have an electrical charge in the bottle. :) I got zapped by a new bottle of Transplant a couple weeks ago. :p
:Namaste:
 

InTheShed

Member of the Year: 2018 - Member of the Month: Jan 2018, Nov 2018 - Grow Journal of the Month: Aug 2018 - Plant of the Month: Oct 2018

Amy Gardner

Member of the Month: March 2018 - Photo of the Month: April, Dec 2018, Apr 2019
Well I imagine there is some electrical activity in any soil ... :hmmmm: I wonder if that's true (was only an imagining after all:4:).
 

stoneotter

Member of the Month: July 2019
Here's an example of another informed person/scholar's mention of ph and soil.

"The Ideal Soil Chart (Agricola’s Best Guess v 2.0 January 2014) Based on a Soil Test using the Mehlich 3 method Organic Matter (OM) 2% — 10% Depending on climate pH 6.4 – 6.5 Balance the minerals and pH will take care of itself"
 
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stoneotter

Member of the Month: July 2019
Here's an example of another informed person/scholar's mention of ph and soil.

"The Ideal Soil Chart (Agricola’s Best Guess v 2.0 January 2014) Based on a Soil Test using the Mehlich 3 method Organic Matter (OM) 2% — 10% Depending on climate pH 6.4 – 6.5 Balance the minerals and pH will take care of itself"
Thanks @Amadeus Forzin
 

vtwin906

Well-Known Member
So much incentive for over-thinking a small grow here, omg. But it gives confidence that I can be optimistic about moving into a generic potting mix with an organic fertilizer such as GH BioThrive once I am back on my acre of heaven in just a few more weeks. My well water has less than 20ppm of DS and tastes better than any bottled water I've tasted while living in town over the winter, the plants loved it when I grew years ago. One question I have is whether to add worm casings to the potting mix.... 10%?
 

onewarmguy

Well-Known Member
Well I imagine there is some electrical activity in any soil ... :hmmmm: I wonder if that's true (was only an imagining after all:4:).
Hey, if I can make a 5V battery out of a boiled potato, I'm pretty sure there's some sort of charge in there.

 

UrbanAchiever

Photo of the Month: Feb 2018
Water out of my tap is 8.1 and I have found I no longer have deficiencies since regularly ph’ing my water. Even with living organic soil, which is supposed to balance it out.

If the water was closer to 7, it probably wouldn’t be an issue. 8.1 is too much apparently. The water quality and chemical/mineral composition has a factor in whether or not a person may or may not need to ph. I went 3 or 4 grows without ph’ing my water. The results or differences aren’t incredibly significant, but enough for me to half ass correct the tap water.

Edit* I have been starting to use West Coast Fish Fertilizer, and it actually brings my ph down enough where I barely have to add ph down. So my gentle nutrient additions do some of my correcting.
 

InTheShed

Member of the Year: 2018 - Member of the Month: Jan 2018, Nov 2018 - Grow Journal of the Month: Aug 2018 - Plant of the Month: Oct 2018

UrbanAchiever

Photo of the Month: Feb 2018
High pH is not as significant as high pH and high alkalinity. Do you have a water report from your local municipality UA?

"Of greater concern is the case where water having both high pH and high alkalinity is used for irrigation."
Source
I’m not sure, just checked one of the city reports and the alkalinity is 125mg/Litre.

TDS 163mg/L,
says ph is 7.9 from that well source

Again I haven’t seen much difference with the ph, just less deficiencies. Although I have been adding calmag/fish fertilizer at 1/4 strength on a regular basis so that could be the reason too.
 

Elvin

Well-Known Member
I got tired of paying $110 a month for rural water and hooked up my well to the house's water. My water is drinkable with a nice taste so I've not bothered testing it.
I'm growing in soil not water so I don't bother with pH; I'm pretty sure if one doesn't over-fertilize and always be sure to have a nice amount of run-off everything kind of works out.
 
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