Lithops Cultivating : Lithops like sand, gravel, and just enough soil to hold it together.The soil should drain easily, be mainly mineral based, and should not contain too much organic matter. Your climate also should be taken into account. If your plants are grown in humid or colder climates, drainage is very important, because the water must not remain in the soil for too long. If your climate is very hot and dry, you can have a bit more organic matter, and the soil can be a little more compact, so that the water can remain in the soil for long enough for the plants to absorb the water. When adding compost to your mix, you must ensure it is decomposed properly. I would suggest that you sieve your compost to remove any larger particles. The type of soil mix you use is also affected by your watering regime, and must be kept in mind. The type of soil mix you use is also affected by your watering regime, and must be kept in mind. If you water your plants frequently, then a mix which retains water for too long can be a problem. If you grow your plants hard, a soil mix which has hardly any water retentiveness, can be a problem, even though Lithops are pretty drought resistant. One of the best soils to grow Lithops in is decomposed granite, but this is not always easy to obtain. Too much fine silty sand can be a problem, because it has poor drainage. If your sand is fine, you will need to add some grit, pumice or perlite to the mix. Fine clay based soils are also not a good idea because there is not enough air present, clay has a very strong bond to water molecules, which makes it harder for the plants to "pull" the water from them. In habitat the soils are fairly fine, but in cultivation fine soils can be tricky to work with. It is easier to give more water than it is to take it away.