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intelinside1

Best Soil additive for succulents-Turface, Pumice, Decomp Granite

intelinside1
10 years ago

Hi I was wondering what the best material for mixing with soil to promote drainage is?

I'm guessing not pumice because its expensive and floats to surface.

So for 1. Turface 2. Pumice 3. Decomposed Granite - what are advantages and disadvantages for each?

What is the cheapest in price for buying in bulk?

Thanks!

Comments (16)

  • cactusmcharris, interior BC Z4/5
    10 years ago

    Where for, in the planted-in-ground (PIG) -plants or potted ones? It all depends.

    Pumice is cheap where you are - you just have to find a distributor like Hansen Aggregates where you can buy a portion or more of a cubic yard. And, once pumice is wet, it doesn't float much - you may be thinking of perlite / vermiculite.

    If I could get pumice up here (apparently there's a mountain of it not far away, but I've been unsuccessful so far) that's what I'd use exclusively. Since I can't, it's a Turface/poultry grit/potting soil mix I use.

    DG is by far the cheapest of anything. It's also the heaviest. Aside from a soil amendment (providing you wash the fines from it), it's also a great top dressing for both PIG'd and potted plants.

  • intelinside1
    Original Author
    10 years ago

    edit sorry- yeah i meant to write PERLITE floats
    Pumice is one of the ones that I was thinking of using.

    I guess I was looking for Planted-in-Ground plants and Potted.

    i've been using some sand that is kinda course but also has a lot of dusty fine particles which probably isn't good

  • wantonamara Z8 CenTex
    10 years ago

    Course gritty sand is good in PIG situations but awful in the potted situation. It holds onto water in the pot. Fills i the airspaces. It acts differently in the ground.

  • aztcqn
    10 years ago

    I had posted a request about this very subject, some time back. I wound up repotting my trichos 3 times as the mix was not working well enough each time. In the end I cut in 50% pumice to mix (potting dirt and sand 50/50 I started with which was a very bad idea). This initial mix was incredibly dense and water sat on the surface for awhile before disappearing.
    The pumice really made a difference in drainage. The trichos have since extended happy fat pups which means they have established roots in the final pumice mix.

  • cactusmcharris, interior BC Z4/5
    10 years ago

    aztqn,

    Sand in your mix - bad almost every time everywhere. In SouCal, the 50/50 pumice/soil ration works so well, but if you've found your present mix to be the cat's meow, more power to you.

  • nil13
    10 years ago

    It all depends on what your existing soil conditions are. A lot of SoCal has sandy soil that doesn't really need amending for drainage. Some places here have heavy clay and that would need amending. You have to tell us what your soil composition is (percentage sand, silt, clay) before we can make any recommendations as to what you should add. A simple test can be performed where you take some dry sifted soil, put it in a jar with water, shake, let settle overnight, and then measure the layers.

    You also forgot scoria, lava rock, as an amendment.

  • cactusmcharris, interior BC Z4/5
    10 years ago

    I'd guess that a 70/30 split of DG/screened potting soil or top soil would improve your existing soil a lot so that it's even better equipped to handle succulents. You'd likely get away with putting most of them into the ground as is, but I always liked to slightly improve the ground before putting a plant in. There are a lot of ways to go about this - that's just one of them.

    Another amendment is sand - some might be good, depending on what you're pairing it with, for plants into the ground. I'd stay away from it completely for potted plants unless the grain size is large.

    I don't use scoria because it makes for too-heavy soil, but many people do use it. It's certainly an OK top dressing, both for potted and PIG'd plants, because of its availability and price. I'd use DG though, given my druthers, over scoria for everything.

    This post was edited by cactusmcharris on Thu, Sep 12, 13 at 12:15

  • wantonamara Z8 CenTex
    10 years ago

    A friend of mine amended Oklahoma City clay by adding a huge amount of sand and gravel to it for her landscaping needs. She swears by it in that regard. It was mounded on and her cactus garden in a cold and difficult situation is something to behold. In her pots she does not use it. I have some sand in my pots because I was lazy and did not screen my DG. Those are the slower draining pots.

  • nil13
    10 years ago

    yeah, but in order to properly amend clay soil with sand, you have to bring the sand fraction up to around 70%.

  • wantonamara Z8 CenTex
    10 years ago

    She did . 1 part soil to 1 part sand - 1 part gravel. And more. It was a bout 30 % when she was done with it. She added more sand and gravel and some compost. It was TOTALLY friable. It fell away in your hand. Did not hold a shape when squeezed. It was GRITTY. During the truck loads that she brought in and mounded and worked in process, the neighbors were a tad shocked because it would rain and the washing away of the sand and gravel before things settled in was a bit troubling.

  • wantonamara Z8 CenTex
    10 years ago

    Does the Decomposed granite have clay in it?? This differs around the country. I used a washed decomposed granite compost mixture because I fave found that the unwashed clayey stuff does not drain as much as I like. They have 3 grades of DG. I add a pea gravel or crushed granite to mix into the ground for chunky ness. I also add lava sand and basalt sand for fertilizing reasons. I just leaned that the washed granite has other exotic fertile sands mixed into it. I make soil like a cook who stares at the inside of a refrigerator looking for inspiration. I also recommend the addition of blood meal for the roots . Sometimes I add expanded shale as a pumice substitute. No nitrogen I pile all this on top of broken up construction trash to get a good mound going.

    The guy below adds pine bark to his mixture He has a illustration in the instructions below. I think he used to be in top of Texas gumbo but has moved west. I am not sure what his ground is now.

    $14 per 40lb would be a steel in Texas. You can't find it in Austin. I pay that for Lava sand and more than that for basalt sand.

    I buy my DG and soil products from people who sell bulk ground products. where one can load it yourself or get it by the ton or 1/2 or more cubic yard. google bulk soil products for your area or bulk landscaping supplies. I have a place that lets me load up 10 gallon pots full of stuff in my little car . Yes I am a dirty car person.

    Here is a link that might be useful: Yuccado instructions for dry garden

  • intelinside1
    Original Author
    10 years ago

    Thanks. I bought a 40 lb bag of the pumice for $14 :) It was under the name "Dry Stall" for horses.

    I suppose for the decomposed granite I have to look into it and see the clay content.

    I also did the soil jar test and it looks like I have around 40% sand / 35 % Silt / 25% mix of clay AND organic materials. I think I need to do a test again beause there was so much organic material floating around in the jar I think it messed up the results.

    Also the soil was very dry and hard it nearly broke my shovel LOL. Overall the soil is kind of dark and very hard to dig into or break up. It's almost like digging through rock.

    Also I was wondering if Coffee Grinds would be good for the soil as well? I have a lot of bags that I get free from starbucks.

  • Christopher Hauser
    6 years ago

    Use fine aquarium gravel it don’t have to be crushed granit it’s to expencive

  • rina_Ontario,Canada 5a
    6 years ago

    Christopher

    I find aquarium gravel more expensive than crushed granite. I buy crushed granite in farm supply store; sold as chicken grit and it is only CND $10/50lb bag


    (Btw, this thread was last active in 2013)

  • lisasfbay9b
    6 years ago
    last modified: 6 years ago

    I wonder if Christopher finds aquarium gravel "cheaper" because he can buy it in tiny amounts? I have recommender this for people who just have one plant and only need a half cup or so of gravel/pumice. Also, it's easy, easier, to get since we have a PetCo nearby. I buy my pumice by the truckload, which makes it cheaper for me... since I'm into rabid succulent hoarding without end:-)