Greetings, discerning American gardener. We are Lithops, the humble "living stones" you have chosen to nurture. To truly thrive in your care, we require a very specific home for our roots. Our survival in your climate, so different from our native South African deserts, hinges entirely on the medium you provide. Please, listen to our needs.
Our greatest fear is not drought, but moisture. Our roots are supremely adapted to absorb a burst of water and then exist in utter dryness. When water lingers, it spells our doom through rot. Therefore, our soil mix cannot be soil at all in the traditional sense. It must be a gritty, porous, and utterly inorganic-dominated substrate. Think of it as a rocky anchor that allows water to vanish within seconds of watering, leaving only a hint of humidity for our roots to find.
We dream of a mix that is roughly 80-90% inorganic, sharp-edged grit and only 10-20% organic matter. The inorganic components provide the structure and drainage we crave. The best choices are poultry grit (crushed granite), pumice, and coarse perlite. Pumice is superior as it is porous and provides some moisture retention without sogginess. Perlite is good but can float to the top over time. Avoid rounded materials like pea gravel, as they don't create the necessary air pockets. For the minimal organic component, a sifted, well-decomposed cactus & succulent potting mix is acceptable. Its sole purpose is to hold a tiny amount of nutrients and a minuscule amount of moisture—just enough for our brief drinking window.
Our roots are accustomed to the mineral-rich, slightly acidic soils of our homeland. A neutral to slightly acidic pH (around 5.5 to 7.0) is ideal for us to properly access what few nutrients are available. This is another reason to avoid limestone-based products like some clay soils, which can make the environment too alkaline. The inorganic components we prefer, like granite and pumice, are generally pH-neutral, providing a stable foundation.
To create the ultimate abode for us, please combine the following, which are readily available at garden centers, farm supply stores (for poultry grit), or online:
• 2 parts Pumice (1/4" size or smaller)
• 2 parts Poultry Grit or crushed granite
• 1 part coarse Perlite
• 1 part sifted Cactus & Succulent Potting Mix (sift out the large woody chunks)
Mix these components thoroughly while we are bare-root. Before potting us, slightly moisten the mix—just enough to keep the dust down. This will also encourage our roots to immediately seek out the faint moisture and begin establishing themselves. Plant us in a terracotta pot, which breathes and helps wick away excess moisture, with a generous drainage hole.
