Why does cactus store water


The nutrition of the plants in the desert

In the arid climate, the release of minerals from the soil plays a very important role. It is not uncommon for them to come from former marine deposits. These are dissolved by water and transported to the surface through its evaporation.


So on the surface, not inconsiderable concentrations of salts accumulate, some of which are used to nourish the succulents. The drier, the less organic matter is formed and also converted and the less it plays a role in plant nutrition. This can also make it understandable why some cactus species do not tolerate humus well at the roots (e.g. Lophophora williamsii) and are downright damaged, the humic acids corrode their root tips.


The high salt tolerance of many succulents can be understood from the following example: in arid regions precipitation falls rarely but very heavily and in large quantities. In turn, the superficial salt accumulations dissolve in the water and are flushed into sinks where the water evaporates and the salt remains. Only samphire, so-called halophytes (salt plants) can survive in these salt pans. However, cacti (Ariocarpus) found under such conditions.


Lightning can cause air nitrogen to reach the earth, chemically combined with rainwater. The little rainfall in arid areas often comes in the form of violent thunderstorms, so this form of nitrogen input is not insignificant.


In addition, special microorganisms that only exist in natural arid soils play an important role in the extraction of nutrients. Unfortunately, these cannot be artificially cultivated to this day.


Knowledge of the natural conditions makes it clear that, contrary to popular belief, adequate fertilization with mineral fertilizers largely corresponds to the natural conditions of succulents.


> Practical tip 'Fertilizing & Watering'


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