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mike69o

Cactus and the gritty mix - Questions

I have a few cacti that need re-potting from their nursery pots and I would like to put them in the gritty mix. I am just wondering if there is anything special I should be doing or just treat them just like any other plant.

I have FP for fertilizer and some of the other plants will start getting some Pro-Tekt for the summer. Should I use the same for my cacti?

Thanks
Michael

Comments (22)

  • drew51 SE MI Z5b/6a
    9 years ago

    The gritty mix is just about right for cacti, probably the only plant I would grow it it. I use DE instead of turface, it holds more water, and has larger pores that plant roots can actually utilize. Cacti like an acidic environment, don't use any lime. Here is one of mine in regular potting soil. A Gymnocalcium. I have had this one for about 30 years.
    {{gwi:32386}}
    For fertilizer I use Ammonium sulfate and Miracle Grow when it's growing. Never added trace elements in 30 years.
    It's already in most potting soils that are really soil, and not soilless. I was never much of a fan of dead soilless mixes.
    I do use beneficial fungi and bacteria. The AS fertilizer maintains an acidic environment. I use 1/4 teaspoon of both at most watering times. Mixed in 2.5 gallons. Sometimes when I can't water frequently due to cold or cloudy weather I will give a full dose. I like to give one full teaspoon a month of both fertilizers from April through September.
    Dose was determined from a scientific study done on cacti.
    Schultz All Purpose Water Soluble Plant Food 20-20-20 is actually the exact dose required with AS. I'm using MG right now as it is on hand.

    I have had this one for 41 years.
    {{gwi:32387}}

    But feel free to listen to people whom never grew a cactus in their life.Tell you what you should use. Each plant has specific needs. None of my plants are treated the same. Soil, PH, and fertilizer all vary. I have about 10 fertilizers I use. Most requirements were determined from experience and research of scientific studies.
    Having said that the fertilizers you mention are very good products and will work fine. But I would find a way to maintain an acidic environment. You could use sulfuric acid, citric acid even vinegar in your water to maintain that environment. You would need a PH meter though to acidify water properly. A PH of 5.5 in the water would do fine.

    This post was edited by Drew51 on Fri, May 30, 14 at 2:30

  • aztcqn
    9 years ago

    Hi!
    Just happened upon this thread and became intrigued.
    Drew51 that gymno is so beautiful!

    If I may ask, what is:
    FP fertilizer
    AS fertilizer
    and MG?

  • drew51 SE MI Z5b/6a
    9 years ago

    FP is Foliage Pro, a decent fertilizer.
    MG is Miracle Grow
    AS is Ammonium Sulfate pure nitrogen with sulfur which makes it very acidic 21-0-0. Easy to kill plants with this stuff, but very useful for cacti and blueberries. I use it to drop PH quickly, and it works great! It can be used on brambles too (raspberries, blackberries) but better more balanced organic fertilizers make more sense there.Like Hollytone. I use it on young brambles that are actively growing to get them up to size quickly. On mature brambles I would not use it. They grow fast enough already!
    Here's one of three bramble patches I have
    {{gwi:32388}}

    Yeah that Gymno is great, you rarely see any that big, it is really old!
    {{gwi:32389}}

    This post was edited by Drew51 on Fri, May 30, 14 at 4:52

  • greenman28 NorCal 7b/8a
    9 years ago

    Drew, you have no idea about the efficiency of the Gritty Mix or the 5-1-1 as you have never used them.

    With so many folks growing successfully in these two mixes, it's hard to take your aggressive and bitterly jealous comments with a straight face.

    Try sharing your ideas without the vitriol.

    Josh

  • Michael O (USDA Z9 San Tan Valley AZ)
    Original Author
    9 years ago

    Nice, so my thread went to ....and no info on the questions I had. Oh, well...

  • greenman28 NorCal 7b/8a
    9 years ago

    Mike, you'll notice that any mention of Al's mixes draws ire from this one person in particular...which isn't helpful in the least.

    That said, you are on the right track. Proceed just as you planned. When fertilizing, just reduce the strength of the dose, 1/8 to 1/4 strength, depending upon how frequently you are fertilizing. Pro-TeKt is not needed, but I do have a bottle that I use every once in while.

    When you make your Gritty Mix, wet it thoroughly. Saturate the bark and re-pot with the mix moist. Then, wait 3 - 5 days to water again.

    Josh

  • Michael O (USDA Z9 San Tan Valley AZ)
    Original Author
    9 years ago

    Thanks Josh, that sounds very good. I usually fertilize once a week, so maybe 1/4 strength would be good. I feel a bit more confident now. :)

    Michael

  • Joe1980
    9 years ago

    Mike, I can assure you that you'll do great. I was quite skeptical in the past about growing in what looks like pea gravel, but it seemed to be all the rage, so I took the plunge. Not to mention Al has some very good explanation and science behind his mixes and why they work. Well, I can attest to the fact that the gritty mix does indeed work, for both succulents and tropicals. I will not take away from Drew's abilities, as it is quite impressive to have kept any sort of plant alive for 40 years, but going on the attack before anyone responds, at least for me, makes me take take his response with a grain of salt. I can assure you though, that Al (Tapla), and Josh (greenman28) will lead you down the right path, as they both have done for me. I, like Josh, am a jade enthusiast, and my jades are doing excellent since putting them in the gritty mix. I have a few tropicals in gritty mix that are thriving as well.

    Joe

  • Michael O (USDA Z9 San Tan Valley AZ)
    Original Author
    9 years ago

    Joe,

    Thanks for encouraging words, I truly believe the gritty mix and the 5-1-1 work and it all makes sense to me. That's why in the original question I mentioned the gritty.

    I've been reading quite a bit for the last month or so about all the mixes and gathered all the ingredients, so yesterday I re-potted a couple of plants and today I am staring on my succulents. Just received a bare root Agave Potatorum and potted in the gritty. Again, thanks, I appreciate all the encouragement I received and all the help.

    Michael

  • jodik_gw
    9 years ago

    I use various renditions of the Gritty Mix for ALL my indoor plants, with great success... from orchids to cacti!

    It's true... Al and Josh will lead you down the right path, with lots of help along the way!

  • Michael O (USDA Z9 San Tan Valley AZ)
    Original Author
    9 years ago

    I wanted to take a picture of my first succulent in the gritty mix. So here it is. Agave potatorum potted on Friday.
    First wattering tomorrow morning. The mix was wet when i potted it.

  • greenman28 NorCal 7b/8a
    9 years ago

    Mike, the bark looks a bit large (or perhaps the Turface small?)....did you screen the bark to 1/4 inch?

    Josh

  • Michael O (USDA Z9 San Tan Valley AZ)
    Original Author
    9 years ago

    Josh, I screened the bark thru 1/2" screen but most pieces are smaller. I read on one thread that the pine bark is OK thru 1/2" screen.

    here is a picture of it:

  • nil13
    9 years ago

    I feel that Al's gritty mix holds a bit too much water for cacti. Succulebts are a different story though. For cacti I start with straight pumice and then depending on the species will add some turface if it needs a little extra moisture retention. DE could serve that purpose as well. I also have a bunch in pea gravel with a bit of turface and that works well too. Sometime you just need that extra bulk density that gravel provides on windy sites. Now jungle cacti are a different beast altogether.

  • greenman28 NorCal 7b/8a
    9 years ago

    Mike, you must have conflated the two mixing instructions.

    The Gritty Mix calls for 1/4 inch bark. I would resift the bark for sure.

    Jsoh

  • Michael O (USDA Z9 San Tan Valley AZ)
    Original Author
    9 years ago

    Oh man...I will end up with maybe 20% of a 2 cubic ft bag.
    I can use the bigger pieces in the 5-1-1 right?

    Here is a picture of the barked screened thru 1/4", is this good? Also, should I re-pot the Agave?

    Thanks for all the help Josh, I really appreciate it.

    Michael

  • greenman28 NorCal 7b/8a
    9 years ago

    Looks much better! And, yes, I would re-pot the Agave....it won't hurt it or even set it back, really. Tough plants.

    Josh

  • Michael O (USDA Z9 San Tan Valley AZ)
    Original Author
    9 years ago

    Thank You Josh, I will.

    Michael

  • drew51 SE MI Z5b/6a
    9 years ago

    My goal is to grow robust healthy plants. Use the best possible amendments, amendments that make sense. Broken glass will work, but not ideal. I see the gritty mix as compromised, sure it works, but far from ideal. But to each his own. Experience is a great teacher. This brain cactus is in my own mineral mix. Pumice, DE, river rock, lava rock, pine fines. My wife can't find enough places for her frog statues!
    It's become so big, it broke up a little when putting outside this year. Hard to move it! A quarter added for size comparison.

  • Michael O (USDA Z9 San Tan Valley AZ)
    Original Author
    9 years ago

    OK, Drew51,

    So "my own mineral mix. Pumice, DE, river rock, lava rock, pine fines" What is so diiferent between yours and the gritty?

    So you add pumice, DE (in the gritty), river rock (granite in the gritty), pine fines (in the gritty). Your mix will retain a bit more water...it is still basicaly gritty mix.

    Sorry, I don't get it.

  • Michael O (USDA Z9 San Tan Valley AZ)
    Original Author
    9 years ago

    Josh,

    I have about four Epiphyllum cuttings that I need to start and two Huernia zebrina cuttings. Can I start them in the gritty or the 5-1-1? Any tips on how to go about it? This is going to be the first time I attempt to start from cuttings.

    Thanks
    Michael