The Cal-Mag of my dreams?

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ohugal
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Re: The Cal-Mag of my dreams?

Post by ohugal »

Hi Steve,

What is says on the bottle:
Terra Aquatica - TriPart - FloraMicro - Total nitrogen (N) = 5% / Ammoniacal nitrogen = 1% / Nitrate nitrogen = 4% (detail : molybdenum (Mo) = 0,002%)
So, ammonium (NH4) is outweighed by nitrate (NO3), which in acidic conditions is not a good thing. Nitrate nitrogen is also not preferable in hot conditions, but I read that nitrate must be (is?) reduced to ammonium inside the plant. Is this extra work for the plant when opposed to ammoniacal nitrogen? So it's better not to use this fertilizer on my cacti then?

Here are the full labels:
Terra Aquatica - TriPart - FloraMicro (5-0-1)
Total nitrogen (N) = 5% / Ammoniacal nitrogen = 1% / Nitrate nitrogen = 4%
Potassium oxide (K20) =1,3%
Boron (B) = 0,01% / Calcium oxide (CaO) = 6,0% / Copper (Cu) Chelated EDTA = 0,01% / Iron (Fe) Chelated 6% EDDHA - 11% DPTA 0,12% / Manganese (Mn) Chelated EDTA / 0,07% / Molybdenum (Mo) = 0,002% / Zinc (Zn) Chelated EDTA = 0,02%

Terra Aquatica - TriPart - FloraBloom (0-5-4)
Phosphoric anhydride (P2O5) = 5%
Potassium oxide (K20) = 4%
Magnesium oxide (MgO) = 3% / Sulphuric anhydride (SO3) = 5%

My mix is: 5 parts pumice + 1 part sandy loam + 4 parts quartz gravel/sand
Location
Antwerp, Belgium
temperate, maritime climate with mild winters and cool summers
hardiness zone 8a
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Steve Johnson
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Location: Los Angeles, CA (Zone 10b)

Re: The Cal-Mag of my dreams?

Post by Steve Johnson »

ohugal wrote: Sun Jan 08, 2023 9:41 am Hi Steve,

What is says on the bottle:
Terra Aquatica - TriPart - FloraMicro - Total nitrogen (N) = 5% / Ammoniacal nitrogen = 1% / Nitrate nitrogen = 4% (detail : molybdenum (Mo) = 0,002%)
So, ammonium (NH4) is outweighed by nitrate (NO3), which in acidic conditions is not a good thing. Nitrate nitrogen is also not preferable in hot conditions, but I read that nitrate must be (is?) reduced to ammonium inside the plant. Is this extra work for the plant when opposed to ammoniacal nitrogen? So it's better not to use this fertilizer on my cacti then?

Here are the full labels:
Terra Aquatica - TriPart - FloraMicro (5-0-1)
Total nitrogen (N) = 5% / Ammoniacal nitrogen = 1% / Nitrate nitrogen = 4%
Potassium oxide (K20) =1,3%
Boron (B) = 0,01% / Calcium oxide (CaO) = 6,0% / Copper (Cu) Chelated EDTA = 0,01% / Iron (Fe) Chelated 6% EDDHA - 11% DPTA 0,12% / Manganese (Mn) Chelated EDTA / 0,07% / Molybdenum (Mo) = 0,002% / Zinc (Zn) Chelated EDTA = 0,02%

Terra Aquatica - TriPart - FloraBloom (0-5-4)
Phosphoric anhydride (P2O5) = 5%
Potassium oxide (K20) = 4%
Magnesium oxide (MgO) = 3% / Sulphuric anhydride (SO3) = 5%

My mix is: 5 parts pumice + 1 part sandy loam + 4 parts quartz gravel/sand
This is the chemical analysis for the Dyna-Gro Orchid-Pro 7-8-6:

Image

If I'm reading everything right here, I believe that the Orchid-Pro will be better for you. Hopefully Mike will be able to verify.
If you just want photos without all the blather, please visit my Flickr gallery.
My location: Los Angeles, CA (Zone 10b)
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ohugal
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Re: The Cal-Mag of my dreams?

Post by ohugal »

Ok. Thanks, Steve! I'm (also) going to wait for the remarks of the others. I do really hope the GHE/TA fertilizers are still an option. It's a bit demoralizing at the moment to be honest, although I feel I understand fertilizers a lot better. If I have a time I will probably write down what I've learned to create an overview, which I can consult in the future.
What happens to the plants (the cacti) with this imbalance of ammoniacal and nitrate nitrogen? What does an excess of nitrate do to the roots for example? Is it something which takes time or occurs quite fast?
Steve, since you're most familiar with the Dyna-Gro products, do you mind telling how much I should use of the Orchid-Pro and potassium sulfate stock solution? I only kept notes on the GHE/TA ferts and I don't have the time to look it all up. The calcium-magnesium I'll look at later.
Location
Antwerp, Belgium
temperate, maritime climate with mild winters and cool summers
hardiness zone 8a
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Steve Johnson
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Re: The Cal-Mag of my dreams?

Post by Steve Johnson »

Hi Ohugal,

Since climate factors into how cacti use NH4 and NO3, we'll compare your climate and mine:
  • Your climate -- temperate, maritime climate with mild winters and cool summers south-west facing window in a city appartment. "Cool summers" doesn't say much, so it would be helpful to get a daytime high average number for your spring and summer.
  • My climate -- Mediterranean with mild winters, and I keep the collection outdoors 365 days a year. Daytime highs in the spring are in the 75-85F range, summers generally in the 80s and 90s. Summertime heat waves take the daytime highs up to about 100-105F (even higher in rare instances), although they don't last for more than a week.
The other significant factor is potting medium:
  • Your cactus mix -- 5 parts pumice + 1 part sandy loam + 4 parts quartz gravel/sand. Pure sandy loam is inorganic and therefore mineral. However, I don't think pure sandy loam exists in the real world, so I'm pretty sure that you do have some organic material in yours. If that's the case, your mix is probably pH-neutral or slightly acidic. The only way to know for sure is by running a test per Jerry's instructions:
    jerrytheplater wrote: Fri Jan 06, 2023 10:11 pmThe proper way to test the pH of soils of whatever type is to take a good representative sample of the "soil" you want to test and place it in a clean non reactive container. Add enough Distilled Water to cover the sample by a few inches and stir well until everything is wetted. Let it soak for a few hours and then test the pH. If using electronic pH meters, you can place it in the water as long as you don't damage it by contacting the "soil". Filtering is acceptable.
    By the way, the word "sand" sends up a red flag. If it's coarse builder's sand, okay. If it's fine "playground sand", not okay because it'll settle down and turn into a brick after repeated watering and drying out.
  • My mix -- I already know that my hydroponic pumice and granite gravel mix is slightly alkaline, although nothing like the alkalinity of desert soils.
Put both factors together on my side (spring/summer heat + hydroponic mix), and this seems to favor the GH FloraMicro over the Dyna-Gro. Put those same factors together on your side, and IMO the Dyna-Gro Orchid-Pro is the best you can get.

You're asking 3 good questions, and I'll take them in order:
ohugal wrote: Sun Jan 08, 2023 11:11 amWhat happens to the plants (the cacti) with this imbalance of ammoniacal and nitrate nitrogen?
First, let's remember what we jut learned from Mike:
MikeInOz wrote: Sun Jan 08, 2023 1:16 am...( Note.. nitrate must be reduced to ammonium inside the plant before it can be used. Without molybdenum, nitrate it can build up in plants so it must not be left out of fertilizers)...
You and I both have Molybdenum (Mo) in the GHE/TA and Dyna-Gro ferts -- apparently the trace amount of Mo is all that's needed. It also means that nitrate-to-ammonium reduction inside the plant is a relatively slow process aided by the Mo.
ohugal wrote: Sun Jan 08, 2023 11:11 amWhat does an excess of nitrate do to the roots for example? Is it something which takes time or occurs quite fast?
A basic principle of toxicology -- "the dose makes the poison". If we're putting too much fertilizer into the watering solution, the dosage will be poisonous to our plants. Good news is that it can take a long time (generally speaking, at least 5 years) to see the clearly negative effects on our cacti. The bad news is that we will eventually see it. I look at this in terms of the watering solution's nutrient parts-per-million, so I'll give you a basic breakdown on what I've been doing:
  • 1/2 tsp. Dyna-Gro 7-7-7 per gallon of water
  • 60 ppm N broken down as 18 ppm NH4 and 42 ppm NO3. Here's the math thanks to a good correction I received from 4d3d3d3:
    4d3d3d3 wrote: Sun Jun 12, 2022 7:54 pm
    Steve Johnson wrote: Sat May 28, 2022 9:34 amI'm diluting 1/2 tsp. Dyna Gro 7-7-7 per gallon of water, and here are my ppm calculations for the N, elemental P, and elemental K being taken up by the cacti:

    1/2 tsp. goes into a gallon 1536 times
    N .07/1536 x 1,000,000 = 46 ppm
    P .03052/1536 x 1,000,000 = 20 ppm
    K .0581/1536 x 1,000,000 = 38 ppm
    NPK total = 104 ppm.
    You're assuming the density of the fertilizer is the same as that of water, but it's slightly higher. Dyna-gro 7-7-7 has a specific gravity of 1.3, meaning each mL of fert is 1.3 g.

    0.5 tsp = 2.5 mL, so 0.5 tsp of fertilizer weighs 0.5 x 1.3 = 3.25 g.
    7% of this is 3.25 g is "N", so 7% x 3.25 g = 0.2275 g of N = 227.5 mg of N

    PPM = mg of solute / kg of solvent = 227.5 mg of N / 3.785 kg (the weight of 1 gal of water) = 60.1 ppm of N. Basically what you got if you multiply 46 by 1.3, the density of the fertilizer.
If you use exactly the same dilution of the 7-8-6, you'll get 22 ppm NH4 and 38 ppm NO3 in your watering solution. At that low level, the dose won't make the poison unless you fertilize too often. All things considered, I'm not sure if that would be true about the FloraMicro. In case persistent mild over-fertilization might be a problem, flush your pots with distilled water or rainwater and nothing more once a year in the growing season. (I suppose it doesn't matter if we do it in spring or summer, but I usually flush my pots in early July if I do it at all. I really need to be more consistent about that.)
ohugal wrote: Sun Jan 08, 2023 11:11 amSteve, since you're most familiar with the Dyna-Gro products, do you mind telling how much I should use of the Orchid-Pro and potassium sulfate stock solution?
I'd like to do this as a "package deal" for you, so here's what you and I need before we can proceed:
  • The volume capacity of your watering container. I'll need that to calculate the correct dilution of the 7-8-6. You'll need a container of the same capacity to prepare a Potassium sulfate stock solution.
  • Potassium sulfate in powder form. I use 0-0-52 for my stock solution -- if you can only get 0-0-50 or 0-0-53, I can make the adjustment on what you'll need for your stock solution.
  • A digital kitchen scale for precise measurement of the Potassium sulfate going into your stock solution. A scale reading in 10ths or 100ths of a gram will be more precise. If you don't already have one, kitchen scales aren't all that expensive.
Once I have everything on the list, I'll take you through all the steps. And unless Mike says otherwise, the Dyna-Gro Orchid-Pro will be the right fert for you and your cacti.
If you just want photos without all the blather, please visit my Flickr gallery.
My location: Los Angeles, CA (Zone 10b)
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ohugal
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Re: The Cal-Mag of my dreams?

Post by ohugal »

Hi Steve,

TEMPERATURE 2022 (average max. temp. & max. temp.)
March 56,6°F/67,6°F
April 58,1°F/69,4°F
May 20,2°F/68,3°F
June 72,5°F/90,6°F
July 76,2°F/100,5°F
August 80,2°F/90,5°F
September 67,2°F/87,6°F

SOIL MIX
Regarding to the quartzsand/gravel, definitely coarser than builder's sand. They're practically small stones (with soft edges). They're not spherical, but if I should put a diameter on it, it would be 5/64 or 1/8 inch on average.
The pumice is sieved to remove the small particles/dust.
The sandy loam, I have not tested it to determine what type is. I purchased it as sandy loam.
I will indeed test the Ph as soon as I have calibration solution again (according to Jerry's instructions.)

WATERING/FERTILIZER SOLUTION
I use the metric system, so if you give me your ratio's I'll convert them. I forgot how much water I use at peak growing periode, but it must be something around 2,5/3 liters. I did acquire a few more plants since the summer though.
The potassium sulfate in powder form I'm planning to buy is 0-0-52. I have the following written down for the stock solution: 9,24gr potassium sulfaat (0-0-52) + 5l water (dist.)
I have a pocket scale which is 0,1g precise.

Thanks!
Location
Antwerp, Belgium
temperate, maritime climate with mild winters and cool summers
hardiness zone 8a
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Steve Johnson
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Re: The Cal-Mag of my dreams?

Post by Steve Johnson »

Hi ohugal,

No "play sand" in your mix -- good, and you're all set there. I'll give you the full details on my setup so you can translate my US measures into the metric measures you'll be using. I'll post the info to you over the weekend if not before. Unfortunately you have a rather short growing season for cacti, don't you?
If you just want photos without all the blather, please visit my Flickr gallery.
My location: Los Angeles, CA (Zone 10b)
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ohugal
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Re: The Cal-Mag of my dreams?

Post by ohugal »

Ok. Thanks!
On the short growing season, could be... I don't have too much experience. Our last summer was very hot and sunny, so let's see where climate change takes us. I used a sun calculator to determine the best spot for my cacti upcoming summer and there is indeed a lack of sun most months. The best spot is in the back of the garden. So I'm going to buy a small flat greenhouse to optimize growing conditions. It should be able to house my small collection and give them more exposure and warmth. In 2024 I really aim towards having more species flower and have a more robust growth. The forum definitely accelerated the learning curve!
Location
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temperate, maritime climate with mild winters and cool summers
hardiness zone 8a
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Steve Johnson
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Re: The Cal-Mag of my dreams?

Post by Steve Johnson »

Hi ohugal,

Here are the details.

Potassium sulfate stock solution calculated for use with Dyna-Gro 7-8-6

8 grams 0-0-52 Potassium sulfate powder
1 gallon jug of distilled water or rainwater (not tap water! RO water is acceptable.)
Fill the jug halfway and add in the powder, then fill again until the water is at the fill line. Cap the jug. Potassium sulfate powder doesn't dissolve instantly, so give it plenty of time to go into solution. The jug accommodates my gas oven, and to speed up the process, I set it to 150F and let it go for 1/2 hour. Then I turn off the heat and let the jug sit in the oven for an hour or so. When I bring it out, the water is back down to ambient temperature. Once the Potassium sulfate goes into solution, it stays in solution.

1-gallon jug of watering solution

Fill halfway with water. Add 5 fluid ounces (148 mL) Potassium sulfate stock solution and 1/2 tsp. (2.5 mL) 7-8-6, then fill again until the water is at the fill line. Cap the jug, shake well, and water away.

1 gal. = 3.8 liters -- I'm calculating 2.1 grams 0-0-52 Potassium sulfate powder per liter for your stock solution, so you can use that according to your stock solution container's volume capacity. I also came up with a more precise calculation for your watering solution:
  • 39 mL/L Potassium sulfate stock solution, .65 mL/L 7-8-6.
Make sure that your stock solution and watering solution containers have a fill line.

The spring/summer growing season begins when overnight lows are consistently above 54F/12C and the daytime highs are consistently above 75F/24C. Consistency is important, so when those numbers move consistently in your favor, your cacti will be ready for regular watering and fertilizing.
ohugal wrote: Mon Jan 09, 2023 7:49 pmSo I'm going to buy a small flat greenhouse to optimize growing conditions. It should be able to house my small collection and give them more exposure and warmth.
That would be wonderful! If you can do it in time, your 2023 growing season won't be as short as it has been for your cacti.
If you just want photos without all the blather, please visit my Flickr gallery.
My location: Los Angeles, CA (Zone 10b)
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ohugal
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Re: The Cal-Mag of my dreams?

Post by ohugal »

Noted. Thanks!
Location
Antwerp, Belgium
temperate, maritime climate with mild winters and cool summers
hardiness zone 8a
Panu
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Re: The Cal-Mag of my dreams?

Post by Panu »

Steve Johnson wrote: Wed Jan 11, 2023 1:09 am The spring/summer growing season begins when overnight lows are consistently above 54F/12C and the daytime highs are consistently above 75F/24C. Consistency is important, so when those numbers move consistently in your favor, your cacti will be ready for regular watering and fertilizing.
While this may be good advice, it would be impossible to grow cacti here. We may have night frosts in early June and then again in end of August. Daytime highs above 25 C... well, few days in a summer. :roll:
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ohugal
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Re: The Cal-Mag of my dreams?

Post by ohugal »

Perhaps Patagonian cacti? Not sure.
What do you grow then?
Location
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hardiness zone 8a
Panu
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Re: The Cal-Mag of my dreams?

Post by Panu »

I grow numerous species, genera and hybrids, no problems. Of course most of them are in the greenhouse. However, some are outside, only covered from rain. I overwinter them inside (cool place) and they are outside/greenhouse for 4-5 months (May-Oct).
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Re: The Cal-Mag of my dreams?

Post by Steve Johnson »

Stupid question, but I need to ask anyway...

Does 1 gram of 0-0-52 Potassium sulfate powder contain .52 g K2SO4 and .48 g filler? The answer should be helpful since I'm not sure if 7 g per gallon of water for my stock solution is correct.
If you just want photos without all the blather, please visit my Flickr gallery.
My location: Los Angeles, CA (Zone 10b)
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Re: The Cal-Mag of my dreams?

Post by jerrytheplater »

Steve Johnson wrote: Mon Jan 16, 2023 8:28 pm Stupid question, but I need to ask anyway...

Does 1 gram of 0-0-52 Potassium sulfate powder contain .52 g K2SO4 and .48 g filler? The answer should be helpful since I'm not sure if 7 g per gallon of water for my stock solution is correct.
It contains 100% Potassium Sulfate Steve. Perfectly pure K2SO4 contains 52% by weight K2O as labeled in the US.
Jerry Smith
Bloomingdale, NJ
45 inches (114 cm) rain equivalent per year, approx. evenly spread per month
2012 USDA Hardiness Zone 6b: -5F to OF (-20C to -18C) min.
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Steve Johnson
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Re: The Cal-Mag of my dreams?

Post by Steve Johnson »

jerrytheplater wrote: Mon Jan 16, 2023 9:50 pmIt contains 100% Potassium Sulfate Steve. Perfectly pure K2SO4 contains 52% by weight K2O as labeled in the US.
Glad I asked, and this question get me to what I'm after:
In 100% K2SO4, what are the percentages of elemental K and S? That's what we really need to know -- as MikeInOz pointed out when he taught us about fertilizers, Oxygen is required for the plant's health, but it has no nutrient value on its own.
If you just want photos without all the blather, please visit my Flickr gallery.
My location: Los Angeles, CA (Zone 10b)
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