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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

Well-Known Member
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

Well-Known Member
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%?
 
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