The purpose of this thread is to share soil mixes for containers and discuss the ingredients that make them work. Various people have asked the same questions in separate threads, so I was hoping we might consolidate the best answers in one place. I would like to ask everyone to please stay on topic so this can be the most useful resource.
Please tell us what soil you use for your succulents, and what you would recommend to others. It would be ideal if long-time growers spoke up, because you have the years and experience to know what really works. I would like to make this thread a sticky so that it can be consulted by other folks who may be new to the forum.
My preferred mix at the moment is 50% pumice, 25% cocofiber, 25% bagged generic potting soil (mostly compost). The pumice is screened to a range of about 0.1-0.25 inches, and all three ingredients are moist when I mix them.
I grow a pretty wide range of cacti and succulents including lots of aloes, agaves, Euphorbias, Dudleyas, Echeverias, and Aeoniums. Our climate is mild and dry (10 inches of rainfall), with most of the rain coming during winter. I use this soil for both indoor and outdoor plants, and only a small fraction of them are in unglazed clay pots.
For new growers I would recommend any decent potting soil mixed with an equal volume of pumice, perlite, or gritty equivalent (eg. screened river sand or lava rock, not fine sand). The products on the market which are sold as "cactus and succulent soil" may represent an improvement over regular potting soil as a standalone product (and I have used them successfully in the past), but virtually all of them (with a few exceptions) would benefit from some rock added to a final amount of about 50% inorganic. You may need more inorganic in the mix if your plants experience regular rainfall, or if they are particularly susceptible to rot.
