You'll probably have to make it yourself. Easiest way is to mix one part organic compost (composted bark, composted wood chips, forest humus, just NOT peat-moss) with one to two parts drainage material (pea-sized gravel). For the gravel, pumice is popular, but almost impossible to find on the east coast. However, if you live in area where horses are common, you can sometimes find pumice sold as "Dry-Stall" at well stocked feed stores. Personally, I prefer decomposed granite or cinders as my drainage material, both of which can easily be found at most landscaping materials warehouses.

this is from the container forum succulent soil mix
here is another useful link Container Soils - Water Movement & Retention V

I'm very picky about my cactus and succulant mix and therefore buy a large bag of Supersoil for cactus and succulants, drains great and the plants just love it. I've played with other brands before but they are too rich and the cactus gets mushy or just doesn't produce. I also mix it with Supersoil potting mix for my rose cuttings with a bit of vermiculite.

Thanks for all the help.

You can get unpainted fish tank gravel for your extra drainage material. Petsmart has big bags of it. It's a bit small than pea gravel which I think works well for smaller pots. I also use OilDri (bought at Sam's Club). It is fired clay and hasn't decomposed in my pots in two years. I use it straight for some of the plants and mixed with pinebark fines for others. It is very naturally colored as well with grey and brown pieces.

I use the OilDri as well. For me, it's superior to perlite for the gritty component of the mix. I'm trying it now in my outdoor pots and troughs for the 'winter hardies'. So far-so good. :)

Dave
Milwaukee

Make sure you sift the OilDri or buy a mesh straier. Put the OilDri in the strainer and rinse off with water before adding it to whatever mix. It has a lot of dust in it that will settle to the bottem of your pots with each watering.

I have never heard of Supersoil and I have never heard of a STORE BOUGHT soil that was worth anything, but that is here in Texas. I mix my own. Two years ago I used a variation of Al's regular mix in which I still put a little peat. For my repotting this year, I am using his succulent mix. The OilDri takes the place of the Turface as it is a fired clay. I have grown some stuff in pure OilDri. You have to water a little more frequently and used the Schultz Liquid Cactus Fertilizer mixed at half strength. I always watered with this. The succulents were in mame bonsai pots about 1 1/2" by 1 1/2" in size. This year, I am using Al's succulent mix. I think it will work great!