When we hear the word “desert” we usually imagine Sahara or Kara-Kum with their scorching sand-dunes devoid of any vegetation. But the soil of stony deserts of Central and South America is very rich in all necessary salts for cacti. Though its contains very little amount of humus, water dissolves salts and the plant can absorb them.
But if rains are extremely rare here, where does water comes from? Plentiful dews, falling at night and flowing down between ribs of cacti, the night fogs accumulating on prickly stalks – this is a poor water diet of desert types of cactus growing in Mexico, Peru, and Ecuador.
Roots of many cacti of these places are radish-shaped and are capable to save water within, or ramify widely near the surface. To reduce moisture evaporation, cacti aspire to curtail the area of the stalk surface. That’s why they have either spherical or a short cylindrical form.
Desert cactus types are not afraid of burning sun: some of them have thick and dense thin skin, which becomes flat and “hides” in the ground for the period of droughts; some have high sharp ribs causing shade; others are covered with dense prickles or setae, looking like a brush.
For their correct development desert types of cactus require much sun, soil containing little humus and careful watering. They can easily die because of water stagnation in the ground even during summer heat.






Every year different types of cactus plants and succulents become more and more popular as house-plants. And it can be easily understood: the variety of extraordinary forms of these plants, their slow growth, their unpretentiousness and relative resistance to insects and disease have contributed to their popularity in flats and houses.
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For my collection I prepare the following mixture: leaf mold, clay soil, coarse sand, charcoal and broken brick (2:2:2:1) mixed with one teaspoon of slack lime and superphosphate. Leaf mold is rich in nutrients that are necessary for succulents. Moreover it’s friable and light and absorbs water well. It dries up quickly and prevents water stagnation in the pot. Clay soil (or garden loam) retains water and dissolved nutritive salts perfectly. Its tenacity and thickness plays a large role by planting of high and big cacti. Coarse sand makes the soil loose and porous. It’s an obligatory component of the soil for all cactus plants. Charcoal has an antiputrefactive action. Broken brick is of double importance. First, it’s pieces make the soil porous. Second, it’s very hygroscopic and absorbs superfluous water. Slack lime is necessary for the right metabolism and normal assimilation of nutrients. Superphosphate acidifies the soil, which is very useful for cacti.





