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Alabama Adventures: Longleaf Pine Treasure Forest

After hearing about Pinus palustris from several southern botanist friends, I had to see the trees for myself! I had the great pleasure of ...

12 September 2014

Al's Gritty Mix + Succulents

Succulent Mix Tutorial

For months I debated on whether or not I should mix my own potting medium for my succulents. I tried various bagged soils (with some slight amendments), including cacti & succulent mix, with no luck. Everything is just hold too much moisture.

Many of my succulents did okay, but I lost some to root rot and other issues. I found myself very dissatisfied with commercial cacti mix, and I was to the point where I was underwatering since I was afraid to water even lightly.

I believe that succulents are super easy to take care of -- once you establish them in the right soil. Overwatering is a common mistake, even with plants that love moisture. Well-draining soil is of utmost importance!

In these last few months I've done my research, and as far as custom-mixes go I've seen the same thing pop up over and over again: Al's Gritty Mix. If you frequent the GardenWeb forums you'll often see Al's (username tapla) posts. He is extremely helpful and knowledgeable.

Many people have given his mix a try (and Al doesn't seem to have any reason to tout it -- if he didn't think it was good then he wouldn't suggest it, since he isn't making money off of it), and swear by it. It took me this long to get around to trying it out because I just didn't want to have to hunt for the ingredients.

Succulents grow in places where they get very little water. Sticking these plants in pots indoors for the rest of their lives makes them more vulnerable to problems. I know the mix seems a bit odd to stick any plant in because it is soil-less, but the mix was made after thorough research as well as trial and error with other mediums.

Here are some of my plants in the gritty mix:

Baby succulents in Al's gritty mix

Close-up of Al's gritty mix in pots

Before I post the recipe and what I did, please keep in mind that the credit for all of this goes to Al, and all I did was compile the information that I found into a blog post. Also keep in mind I had to substitute ingredients. My intentions are to help others and to share what is working for me: a yardless, balcony-and-patioless, apartment-dwelling lady in North-East Illinois. My problem for these past few months has been soil that doesn't drain and roots that are rotting, so this is a good solution for me. The mix is customisable so you can alter the equal parts to match your plants' needs! You aren't limited to just using this stuff on cacti and succulents.

If your plants are doing just dandy then maybe you would do better to keep on doing what you're doing. If it's not broke, don't fix it...right?

Issues aside, I decided to give the gritty mix a try based not only on Al's extremely informative posts, but also because I've seen so many people swear by it. I highly recommend that you follow the links I posted above and do your own research, and ask questions on the GardenWeb forums if you have any. The people there are so helpful and kind.

The gritty mix (when made correctly) will do what Al says it will do. If you don't have the correct ingredients in the correct sizes or if you don't make the parts equal, you won't get the same results. After all, if you dump in the wrong ingredients for a cake, or the wrong amount of each, or you bake it too end up with a failed attempt.

If you find making a custom mix, more frequent watering, and etc. too tedious: keep in mind those are your personal preferences based in your experiences and habits as a gardener (which is perfectly fine). That does not make the mix bad. If you are willing to sacrifice initial convenience for an awesome mix, then I think you will join the ranks of us who love it! Despite the work that goes into making it, the end results make it easier to grow happy, healthy container plants.

So that being said, without further ado, I present to you:

Al's Gritty Mix

1 part Turface
1 part uncomposted pine (or fir) fines
1 part Gran-I-Grit Grower's size (or #2 cherrystone)

You will need to sift the finer particles out and make sure that the Turface and grit is about the same size. The bark fines can be a little bit larger if needed. I bought a regular kitchen strainer for $4 at Walmart and separately sifted the ingredients, then measured and mixed; some people use Bonsai sieves or insect screen. Make sure you are careful not to inhale any of the resulting dust when you sift because it is a hazard. You need to do this in a well-ventilated area, and it wouldn't hurt to have a mask handy. 

You can save the smaller particles for compost or for small succulents in small pots. There typically is a LOT of product that won't make it through.

Small particles that aren't suitable to use in the gritty mix

I used this stuff to lay out my succulent leaves and cuttings upon. Some people use it for compost, but feel free to throw it away if you aren't going to use it. 

succulent propagation atop the small gritty mix particles

You also will want to have some sort of screen to keep the mix in the pot, otherwise you're going to have a huge mess. Screen is one option, but I used drywall fiberglass mesh tape and stuck it in the bottom of each pot -- do not get the paper drywall tape!

drywall fiberglass mesh tape

Turface is calcified Montmorillonite Clay and goes by many different names. John Deere has been known to carry it. Turface MVP or Turface Allsport are good. You can also grab some calcined Diatomaceous Earth (DE). It is not the same stuff but it works similarly as a substitute. You can grab some at NAPA (sold as Napa Floor Dry #8222). I actually stumbled upon some turface at O'Reilly when I was looking for DE. They didn't have any DE at that particular store but they had Moltan Safety Absorbent which just so happens to be Montmorillonite Clay. Some carry Moltan Ultrasorb (DE) which is what I was initially looking for. Make sure to test the structure of whatever you buy. To quote Al:

"Not all calcined DE products are created equal. Some are fired at temperatures too low for them to remain stable in potting media. To test, half fill a plastic cup with the calcined DE or calcined clay product & freeze overnight. If it still maintains its structural integrity after thawing, it's fine in container media - with the additional proviso that it contains no perfumes or other phytotoxic additives. You can skip the test if you're using NAPA part #8822 ... it's stable."

The purpose of turface (or DE) in this mix is to hold moisture for the plant to use. It is internally porous and holds a lot of water.

turface safety absorbent

Uncomposted bark fines are also sold as mulch or reptile bark. You can typically find that at Home Depot or any store that sells pet products; Repti Bark is one known brand (if you buy this, the small or medium bags typically have the correctly sized particles. Pine or fir works. You should look for "1/8-"1/4 in size if using fir, or 1/8"-3/8" for pine. Make sure you do not use cedar as they contain tannins and other such growth inhibiting (allelopathic) compounds.

Bark fines provide a little nutrition and water retention, and it is the only organic part of this mix. The fines are internally porous as well, but holds about as much water as the average between turface and grit combined. Eventually these will break down but not too quickly, which is why they are ideal for this mix, so avoid using cocoa mulch. 

Make sure the product you buy isn't much heartwood or sapwood chips! You want it to be the wood similar to Reptibark, which is the outer bark.

Note: This had a little bit of heartwood and sapwood bits, which I picked out. They were much harder than the bark and lightly coloured, so it wasn't hard to tell. I had to stick the mulch I bought in a blender because the pieces were too big, but that's all I could find at the store I went to. I didn't want to drive around too much. After that I sifted out the small particles. I never honestly use my teeny-tiny blender so I don't care what this does to the blades and such; if you like your blender, I encourage you to just find the correct size and save yourself the trouble!

pine bark mulch

Crushed granite sells under the name Gran-I-Grit, look for chicken grit in grower's size. Chick grit is too fine to use. You can find it at a local feed store, or Farm & Fleet. I'm using NatureWise Poultry Grit from F&F, and I noticed they also carried #2 cherrystone. The size should be 1/8"-1/4". Do not substitute crushed oyster shell -- sometimes grit is sold as such or you may think it will be suitable instead based on looks, but its not!

Grit has no internal porosity and only holds a thin layer of water on its surface for a short time.

poultry grit

Once you have collected all of these, you need to sift out the fine particles and combine the ingredients in a ration of 1:1:1. Soak the mix in water before potting. Cut the mesh large enough to cover the bottom of the pot to prevent the mix from escaping. If you hear crackling upon watering, that is just the turface! That is completely normal.

These ingredients combined make a media which allows for water absorption without the saturation, which in turn means little to no perched water. If you've paid attention to any guide to succulent care, the term "fast-draining soil" is deemed extremely important. Well, this mix is perfect for that. You will have to make sure to water frequently enough, and fertilising is recommended -- especially if you're putting other types of plants in this mix. Personally, I'm not familiar enough with fertilisation and so I will not be applying any to my succulents right now. I've read mixed opinions on even needing to fertilise plants even in this mix, but I'm sure to help them reach their full potential, it wouldn't hurt as long as it is done correctly!

Here is what I ended up with after mixing (if you are curious about the dime, its for you to compare size):

gritty mix

Finer particles for comparison:

gritty mix small particles

You should soak the mix well before using, otherwise you are going to have to water quite a bit in the first week to keep it from being too dry. Sometimes the bark can be hydrophobic initially. Make sure to water slowly, pouring water over the full surface. If you have a drip tray collecting the water, once it runs through you want to make sure to dump it out.

The only really downside to this is trying to find the ingredients, the fact that it takes more effort than grabbing any ol' bagged soil, and perhaps your own personal preferences. What it boils down to, is what is easiest for the gardener, vs. what is best for the plants. What I mean by that isn't to say that I think people are necessarily neglecting their plants (a lot of people love their plants as their "babies" -- myself included), but the "best" as in what could give the most potential to flourish.

"A 2-bit plant in a $10 soil has a future full of potential, where a $10 plant in a 2-bit soil has only a future filled with limitations." -Al 

If you try this mix out please let me know how it works for you! Good luck!