A small collection: 2015 and beyond

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bartab
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Re: A small collection: 2015 and beyond

Post by bartab »

Ended up watering a few plants last night and got lucky as the temps dropped down to a bit under 70f. Did the rest of them tonight and all good with the temp already at 67 at 10pm and dropping to somewhere near 61 tonight. Glad I got them all done. I think this is my last feeding with dynagro for this season and will use a 2-7-7 until I stop watering before letting them go dormant. Plan on another month anyways.
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Steve Johnson
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2019 review on hold (temporarily)

Post by Steve Johnson »

The collection has given me an archived embarrassment of riches photography-wise, and I'm about to pile on more when I do the big photo shoot for my 2020 end-of-summer review. The trick is to time it so that I can get everything on camera right before the growing season ends. This is a bigger project than you might imagine, so I'll devote the next couple of weekends to a whole bunch of photography covering each cactus while it's still showing us signs of activity. After the big shoot is done, I'll return to give you the last of my 2019 review. Don't want to lose my audience, though, so I may post a few "tidbit" photos before then. As always, thank you for your interest in what I'm doing here! :D
If you just want photos without all the blather, please visit my Flickr gallery.
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A_G_R
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Re: A small collection: 2015 and beyond

Post by A_G_R »

Great! I really enjoy your post Steve
Alejandro
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Steve Johnson
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More good news and bad news

Post by Steve Johnson »

Might as well get the bad news over with first, and the latest piece of it involves the Mammillaria deherdtiana I'd been doing so well with over the course of 8 years. The north-facing and east-facing sides of the plant on 8/1 and 9/16:

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What the heck happened? First, that 7-day stretch of temps above the century mark in mid-August. What happened next was even worse for the plant -- I remember Keith in Thousand Oaks telling me about losing a Mamm deherdtiana when he lived in Arizona, so I did a search of my forum posts to refresh the old memory on what he said. Yeah, it was from my 2015 end-of-summer review, and here's what he posted:
keith wrote: Thu Oct 08, 2015 2:30 amM. deherdtiana one of my old timers that didn't survive Phoenix AZ , too hot I guess?
Well, Keith, Phoenix came by and paid a visit to my little corner of the world over Labor Day weekend. A whole bunch of pups appear to be dead, and the parent stem may be dead too. However, I won't come to such a drastic conclusion just yet, so I came up with best-case and worst-case scenarios. Here they are:

Best-case scenario -- the dead-looking parts revive themselves, although there's no way it'll happen this late in the growing season. I'll have to wait until spring as I look for the following:
  • Plumping in response to water and/or new apical growth.
  • The setting of buds in March (my deherdtiana has always been reliable about that) -- dead cacti don't bloom, so if I see buds in the dead-looking parts, I'll know that they really aren't dead. This may take place before I notice new apical growth signaling the revival.
Worst-case scenario -- the dead-looking parts really are dead, and if I make that determination, I'll go into disaster-recovery mode. With this view from above, I'll describe what I have in mind:

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Those healthy pups will be "insurance plants", as I do cactus surgery to cut them out and try rooting them. Nice thing is that the biggest pup is about the same size as the parent stem was when I found it as a "singleton" at the California Cactus Center way back in May 2012. And if it has roots, so much the better.

I'd normally give the deherdtiana some occasional light watering in fall and winter, but under the present circumstances, I don't want to chance the possibility of rot after the growing season is done. One thing I know about the plant is that it's opportunistic about growing when the fall/winter season deals stretches of warmth here in SoCal. If it gives me a nice surprise by waking up the dead-looking parts between now and spring, time for some light watering. If it doesn't (and I'm not expecting it will), the deherdtiana will stay dry during fall and winter. Would I dare to unpot it and see what the roots look like in February or March? If I do and the root system is a shadow of its former self, the worst-case scenario will become actionable. I realize that we're talking about a lot of "ifs", but at least I'll have plenty of time to figure out the best course of action as one of those "ifs" turns into a "when".

Next, we'll follow up on good news/bad news post #1 which I discussed here...

The Copiapoa laui in trouble on 9/13 and 9/19:

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The pup on the bottom lost its means of support when the one right on the parent stem's base turned to mush. A few thin scraggly roots weren't enough to keep it going, so I wasn't surprised to see it collapse. The red arrow points to a hole that could be an entry point for rot, and my concern was about what might happen if I watered the plant too soon after the Labor Day weekend heatwave broke. The laui was due for its regular bi-weekly watering on 9/12, but the heatwave intervened, so I decided to give it another week. Watered on the night of the 19th, and let's see the results a week after that:

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There's the good news -- I had nothing to worry about. The plant still looks healthy, and even better is the fact that the pup on the far right is showing some nice activity on its growth point. The laui hasn't been shy about offsetting in the past, so the best result of all would be if it grows new pups to replace the ones that went bye-bye.

After I took down the bedsheet-and-pillowcase arrangement on 9/10, I thought we were done with the worst of it, but Phoenix came back again when the daytime high hit 114(!) last Thursday. I was fully prepared this time when the arrangement went up 3 days prior to the big blast. The highs have been hitting 105 ever since, although the current heatwave is supposed to break on Tuesday, so maybe this really is the worst of it. While I do have good reason to worry about my prized Mamm deherdtiana, further good news may be that I'll get a nicely-extended growing season throughout the rest of October. However, I'm experiencing the kind of extreme summertime heat I've never seen before -- and I hope I'll never see it again.
If you just want photos without all the blather, please visit my Flickr gallery.
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keith
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Re: A small collection: 2015 and beyond

Post by keith »

Hi Steve, its been hot here also. Your Mammillaria dehertiana doesn't look like rot almost like it dried up in the heat ? I had a Escobaria sneedii that did that but the stems that survived are growing and eventually the dead stems will fade away and be over grown by the live stems.

Almost like parts of the roots die. Why IDK ?
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Steve Johnson
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Re: A small collection: 2015 and beyond

Post by Steve Johnson »

keith wrote: Wed Oct 07, 2020 2:36 am Hi Steve, its been hot here also. Your Mammillaria dehertiana doesn't look like rot almost like it dried up in the heat ? I had a Escobaria sneedii that did that but the stems that survived are growing and eventually the dead stems will fade away and be over grown by the live stems.

Almost like parts of the roots die. Why IDK ?
What you just said gave me the idea for another scenario -- maybe not the best, but not the worst either...

The Mamm deherdtiana's root system is healthy enough to support my "insurance" pups, and they're showing touches of fall growth. If it's clear that I'll be dealing with a bunch of dead, dried-up pups in the early spring, I can simply cut them away from the parent stem without having to disturb the roots. If the parent's growth point is also dead, clearing out the dead pups will leave it open and available for growing new offsets along its stem. It's possible that part of the root system did die from the extreme heat, although the only way to know for sure would be to unpot the plant. Instinct tells me that now is exactly the wrong time to do it. My deherdtiana had been perfectly fine going without any water at all over the fall and winter in previous years, so I think this'll be the best course of action -- leave the plant alone until the root system starts regenerating new roots in the spring, no unpotting needed. While playing the waiting game isn't exactly fun in this kind of situation, at least there's hope for the deherdtiana's future.

Don't want to leave y'all without something nice to look at -- my Gymnocalycium ochoterenae vatteri enjoying the latest heatwave on 10/3:

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Last weekend was too bloody hot to do a bunch of cactus photography for my 2020 end-of-summer review, but since we're catching a break from the heat, I'll take advantage of it this weekend. And I just might have another installment of the 2019 review for you too.
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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Steve Johnson
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June blooms

Post by Steve Johnson »

I haven't posted these yet, so to keep things going, here are 3 flowering cacti right on the cusp of spring and summer 2020...

Copiapoa tenuissima on 6/21:

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My "queen of the Astrophytums", A. capricorne on 6/22:

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Can't remember the A. asterias flowering more than once at a time, so this may be its first "twofer" -- going from buds on 6/20 to blooms on 6/22:

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Gorgeous, aren't they?

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I could show you another Astrophytum that bloomed big-time today, but I'll save the shots for the 2020 review. And no, I haven't forgotten about wrapping up 2019, although before we proceed with that, my camera awaits!
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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hegar
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Re: A small collection: 2015 and beyond

Post by hegar »

Hello Steve,
I am trying my best to get my in-ground cacti to grow as well as possible and do read your posts giving advice regularly. I was finally able to persuade my wife to order a 1-gallon bottle of Dyna-Gro All Pro 7-7-7 and have applied the fertilizer a few times this year.
Now I am going to order a quantity of potassium sulfate and also some rooting hormone. You had figured out on another blog I believe, that 1/8 teaspoon per gallon - or was it 2 gallons of water - should be given to cacti. I wonder though, what kind of potassium sulfate you are using. I did go on Amazon.com and there are several brands offered. Most are in powder form and one I did see was advertised as being granular. It would make sense, that the powdered version would be easier to dissolve in water. I do apply all the fertilizer for the cacti using a 2-gallon watering can.
When I applied just ammonium sulfate granules, I had to first place 1 tablespoon of the fertilizer into a quart container with lid and shake it for a while, in order to dissolve the granules. Then I poured the content into my 2-gallon watering can and filled it up with water. Do you need to do the same with the potassium sulfate powder, or does it dissolve easily when water is poured over it?

Harald
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Steve Johnson
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Re: A small collection: 2015 and beyond

Post by Steve Johnson »

Hi Harald,

I get my Potassium sulfate as a powder in 3.5 oz. packets on eBay here:

https://www.ebay.com/itm/Potassium-Sulf ... SwAbxebYaY

Thanks to what I learned from MikeInOz, K should be 1.5 time higher than N, so to be more precise about the amount of Potassium sulfate I add with 1/2 tsp. of the Dyna Gro 7-7-7 per gallon of water, it's 3/32 tsp. plus 1/64 tsp. For 2 gallons, double that to 1 tsp. 7-7-7 and 3/16 tsp. plus 1/32 tsp. Potassium sulfate. I honestly don't know if it would do any harm to round up and make it an even 1/4 tsp. for your 2-gallon watering solution. Maybe not, but if you'd rather not chance it, you can get that precision with mini measuring spoons available on Amazon here:

https://www.amazon.com/Mini-Measuring-S ... 229&sr=8-8

While the Potassium sulfate powder does go into solution, it doesn't dissolve instantly as I had assumed. Here's a trick I discovered -- first, dilute the Dyna Gro in your watering solution and swirl it around a bit. Pour some out into a jar, then put in the Potassium sulfate. Stir until it's completely dissolved, then pour the contents into your watering can. Swirl again, and water away. This brings me to a small advisory on the 7-7-7...

The only problem with the Dyna Gro fertilizers is if they're allowed to freeze. If that happens, the Potassium salt precipitates out and crystalizes. Getting the crystals back into solution is a pain, so the best way to avoid this problem is keep it in the house.
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hegar
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Re: A small collection: 2015 and beyond

Post by hegar »

Hello Steve,
thank you very much for the quick response to my inquiry about adding potassium sulfate to the Dyna-Gro fertilization. I am still a bit confused though about the amounts of which chemical to add to the water. You state, that for a two gallon watering can content I should use 1 teaspoon of Dyna-Gro and then you would add 3/16 teaspoons plus 1/32 teaspoons. Are both of the last two numbers potassium sulfate, and if so, why not just add them up?
Is the split of these two numbers due to the make-up of the potassium sulfate (K2S04) and I have to add more, because the sulfate component has to be compensated for, thus requiring an addition of potassium sulfate? Either way, it seems to me, that most likely a fertilization with 1 teaspoon of Dyna-Gro plus 1/4 teaspoon of potassium sulfate should be sufficient.
Another thing: In one publication - I do not know who posted it or where it was originally posted - I read, that ammonium sulfate should be used for fertilization, because it was the best utilized form of nitrogen fertilizer. I do not know, why urea or the nitrate version were considered inferior.
So I went ahead and purchased a bag of ammonium sulfate. The bonus for me is, that in addition to fertilization the irrigation water is also acidified. We do have a pH of 8.0 according to measurements I made of our tap water.
Would you continue any fertilization with ammonium sulfate or do you consider the Dyna-Gro 7-7-7 adequate? Do you also apply this kind of fertilizer to your cacti. I assume, that you do not, because it would mess up the balance of the fertilizer treatments.

Harald
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Steve Johnson
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Re: A small collection: 2015 and beyond

Post by Steve Johnson »

Hi Harald,

Sorry to make things so confusing, and this isn't easy to explain...

First, you may have seen this before, but in case you haven't, here's a quote from MikeInOz that got things started for me:
MikeInOz wrote: Sat Aug 22, 2020 3:08 amI forgot to mention also that in the US they use the old ''percentage of Phosphoric acid (P2O5) and percent potash'' (K20)) when they quote P and K in the fertilizer.
So when you buy a 10-10-10 fertilizer in the US you are actually getting N10-P4.4-K8.3 of the actual elements. The rest is oxygen, hydrogen and stuff like that.
I checked out the Dyna grow 7-8-6 and they use this system here too. So the actual elements you are giving your cacti are N 7 - P 3.5 - K 4.9. My comments about ratios refer to the actual percentage of the elements so I would now consider the P in the Dyna grow to be good but the N too high and the K too low!
He was referring to the Dyna Gro Orchid Pro 7-8-6. For the All Pro 7-7-7, N is the same (7), but the true amount of P is actually 3.1, and the true amount of K is 5.8. Since the ideal N-to-K balance is a ratio of 1:1.5, we need to bring the K up to 10.5. That's where the Potassium sulfate supplementation comes in. Potassium sulfate contains 43% Potassium, so the K value of our 0-0-52 is actually 0-0-22, and the Sulfur component becomes the minor nutrient that compensates for the mere trace amount of it in the Dyna Gro ferts. (As Mike told me back in August, "Sulfur deficiency shows up as general paleness. A lot of cacti grow in very high gypsum soils (calcium sulphate) so you can imagine how much S is available to them." If we used just the Dyna Gro, pale-looking cacti is what we'd eventually get.)

Having the proper N-to-K balance right is only half of the story, and the other half is knowing the actual amount of nutrients going into our cacti. This can be expressed in parts-per-million. I'll spare everyone the math exercise, so here's the amount our cacti receive when we dilute 1/2 tsp. Dyna Gro 7-7-7 and 7/64 tsp. Potassium sulfate in a gallon of water:

N = 46 ppm.
P = 20 ppm.
K = 69 ppm.

If I rounded the Potassium sulfate up to an even 1/8 tsp., K would be 79 ppm. Harald, if you dilute 1 tsp. of 7-7-7 and an even 1/4 tsp. Potassium sulfate in 2 gallons of water, you'll get the same ppm numbers. Would the additional 10 ppm make any difference to cacti? You and Mike have a professional background in horticulture, but I don't, so I'll leave the answer to you.
hegar wrote: Wed Oct 21, 2020 6:24 pmYou state, that for a two gallon watering can content I should use 1 teaspoon of Dyna-Gro and then you would add 3/16 teaspoons plus 1/32 teaspoons. Are both of the last two numbers potassium sulfate, and if so, why not just add them up?
I go by my mini measuring spoons -- for you that would be 1/8 tsp. measure plus 1/16 tsp. measure plus 1/32 tsp. measure, which adds up to 7/32 tsp.
hegar wrote: Wed Oct 21, 2020 6:24 pmIn one publication - I do not know who posted it or where it was originally posted - I read, that ammonium sulfate should be used for fertilization, because it was the best utilized form of nitrogen fertilizer. I do not know, why urea or the nitrate version were considered inferior.
That was Elton Roberts, who wrote a couple of articles on it in the Cactus & Succulent Society journal many years ago. When I found them online back in 2012, I fell for his so-called Ammonium sulfate "miracle". Turns out the man knew little or nothing about the science behind what he was claiming, so I backed away from supplementing my 7-7-7 with Ammonium sulfate. Doing so upsets the N-to-K balance we're trying to establish with the Potassium sulfate -- the nitrate and ammoniacal forms of Nitrogen in the Dyna Gro ferts are taken up well by cacti, and that's all they need.

By the way, this is just for general reference. I've seen claims at llifle.com and elsewhere contending that some cactus species need high-Phosphorus fertilizers to flower well. That's a myth, and Mike can bust it for us:
MikeInOz wrote: Sat Aug 22, 2020 3:08 amThere have been many trials on this subject and none have found any benefit at all by such high P ratios. But they have found reduced flowering and other problems.
So the N-to-P balance in the 7-7-7 is fine, and the better N-to-K balance is what should promote better flowering for cacti that haven't been flowering normally or at all. I hadn't noticed that problem with any of my flowering cacti, but then again I had nothing to go by. I'll have to find out if it's one of the improvements I see in the next growing season.
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hegar
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Re: A small collection: 2015 and beyond

Post by hegar »

Hello Steve,
once again, thank you very much for clarifying the feeding formula of the potassium sulfate supplement. I shall go ahead now and fertilize my cacti with the Dyna-Gro 7-7-7, using 1 tsp per 2-gallon watering can, plus add 1/4 tsp of potassium sulfate to the mix. That should be fine and close enough to what works best.
I usually water my plants once a week during the hot part of the year and a little less often in the fall. So I am going to add the fertilizer combo each time I do water. We are still having overly warm weather. Just today it was another record for this time, with the temperature reaching 90 degrees F. The normal high should be around 77 degrees F.
I also do have some use for the ammonium sulfate. I am going to add that to my lawn fertilizer. I believe, that you did post the paper by Elton Roberts. As I already mentioned, I am still trying to figure out the best ways of growing cacti and I thought, that Mr. Roberts had convincing arguments. Substituting my then regular Miracle-Gro Bloom Booster fertilizer treatment every once in a while with ammonium sulfate did not seem to do any damage to my cacti. I only used 1 tablespoon per 2-gallon watering can content.
By the way, Mr. Roberts did publish an interesting article in the on-line journal "Cactus Adventures International", October 2020, Volume 32, No. 1, pp. 102-106 about his experiences with excessive amounts of water his Ariocarpus spp. cacti were subjected to. He claims, that not only did practically none of his plants die, but they produced huge numbers of seedling plants! Mr. Roberts also points out, that he had listened to "cactus experts" and then found out, that he had better success growing his cacti than after he adopted the cultivation methods suggested by these experts.

I myself remember, that my horticulture professor told me when I was in graduate school, that sufficient amounts of phosphorus are required, in order for a plant to flower and produce plenty of fruits. That is why I had purchased the 15-30-15 Miracle-Gro fertilizer. Well, I shall find another use for that fertilizer too. After all, I do have a Boston fern, an Aloe and some other foliage plant, plus a Bursera seedling, which I will bring indoors very soon. I could also use it on a Hylocereus sp. plant and a Peniocereus maculatus perhaps.

Harald
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MikeInOz
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Re: A small collection: 2015 and beyond

Post by MikeInOz »

Steve Johnson wrote: Thu Oct 22, 2020 1:15 am

By the way, this is just for general reference. I've seen claims at llifle.com and elsewhere contending that some cactus species need high-Phosphorus fertilizers to flower well. That's a myth,
Steve, I have a couple of trial charts to back that up. I have not seen any data at all suggesting certain cacti need more P to flower well.
The most factor which is far and away the most important for flowering is light. P concentrations in soils in the places where cacti grow are no different to anywhere else.

This one is for two air-filed porosities with various concentrations of N in the mix and added in feeds. As we can see the more N, the longer the time to flowering...(these are not cacti specific but it's the same for all plants)

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This one Phosphorus to Nitrogen ratios. Again, as we can see, the more P in relation to N the fewer flowers.

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This one I may have posted before. It's self explanatory.

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hegar
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Re: A small collection: 2015 and beyond

Post by hegar »

Hello Mike,

before I go ahead and order potassium sulfate I do need to figure out, if my 7-7-7 Dyna-Gro fertilizer is deficient in potassium.
According to the table 16-15 for African Violets, the number of flowers was substantially higher, when there was less potassium added for a K/N ratio of 0.52 (52% potassium), than when the potassium amounted to 83% of the nitrogen. Perhaps I am misinterpreting the table, but that is what it seems to indicate. Also, flowering was enhanced at a very low phosphorus to nitrogen ratio (0.14), which would support what you said about phosphorus not being as important as the other two macronutrients as far as flowering is concerned.
Using the values obtained from that table, my fertilizer should consist of 7% nitrogen, 0.98% phosphorus, and 3.64% potassium for maximum flowering, if I were to grow African Violets.
I admit, I was never very good at math, and chemistry was not my forte either. That is most likely why I cannot quite comprehend, why a 7-7-7 fertilizer would be insufficient as far as the element potassium is concerned, unless the chemical formulation on the label does not truly tell us about the available/present quantity of each of these macronutrients.

I did also find out, that a University of Florida study, and most likely a number more, did support your point of view, that phosphorus is not the main nutrient component for the formation of flowers and fruits.
I used to give hand-outs to my fellow cactus club members, in which I had told them to go with one of the "bloom booster" fertilizers like the 15-30-15 MiracleGro I was using. This advice was based on what I had been told, when I did work toward a graduate degree in horticulture. Well, I guess, the professor was wrong.

Harald
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Steve Johnson
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Re: A small collection: 2015 and beyond

Post by Steve Johnson »

If I may interject...
hegar wrote: Sun Oct 25, 2020 3:19 pmbefore I go ahead and order potassium sulfate I do need to figure out, if my 7-7-7 Dyna-Gro fertilizer is deficient in potassium...That is most likely why I cannot quite comprehend, why a 7-7-7 fertilizer would be insufficient as far as the element potassium is concerned, unless the chemical formulation on the label does not truly tell us about the available/present quantity of each of these macronutrients.
That right there is the problem. For reasons unknown to me, American fertilizer manufacturers go by a different standard than the rest of the world when it comes to telling us the actual amounts of Nitrogen, Phosphorus, and Potassium in their ferts. Since you and I are using the Dyna Gro 7-7-7, we'll use those numbers here.

When you're putting a tsp. of the 7-7-7 into your 2-gallon watering can, 7% is the actual amount of N. 7% is Phosphoric acid (P2O5), but the actual amount of P is 3.1%. 7% is Potash (K2O), but the actual amount of K is 5.8%. Expressed in NPK numbers, the true element values are 7-3.1-5.8. As I learned from Mike, K should be 1.5 times higher than N, so we need to bring the K up from 5.8 to 10.5. Yes, the 7-7-7 on its own is deficient in Potassium, hence the reason for supplementing it with Potassium sulfate.

My math skills are good enough to give you the right measuring amounts of the Dyna Gro and Potassium sulfate that should go into your 2-gallon watering can. However, I freely admit that those skills only go so far, and the ratios in the tables Mike just posted don't make any sense to me. For our purposes, I'm satisfied that we have it right in terms of the proper balance between N and K we're discussing. But is the balance between N and P acceptable, or does the 7-7-7 have too much P in relation to N? It's all about the proper balance, and if the P is in fact too high, the only way to address it would be to add sufficient amounts of Ammonium sulfate on the N side and Potassium sulfate on the K side to the 7-7-7. Mike, what's your take on all this? Unless you say otherwise, we'll stick with what I'm recommending for myself and Harald.

In the northern hemisphere, our cacti are going dormant for the fall and winter. If any watering is to be done, it should be water only, no fertilizer. We'll save the fert regimen for the next growing season.
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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