The substratum soil provides the plant with the nutritional elements necessary for its development. Moreover its different values of acidity, compactness, humidity and water drainage will adapt from time to time to different species. It is therefore necessary to know the specific needs of each species to provide it with the soil it needs. Otherwise the damage will also be rather serious, up to compromising the good development of the plant. The molds are mostly peat or compost based, with small parts of light soil improvers that should help drainage. If too wet, the soil will give problems of water stagnation with root rot and asphyxiation of the plant. Some plants, such as calcicole or acidophilic plants, require particular pH conditions, therefore we will have to make sure that the soil meets these requirements, so that soil improvers such as pumice or lapilli can also be added or removed. Otherwise there will be chlorosis. Finally, if a layer of mulch is missing above the soil, the plants will suffer more heavily in winter frost and summer drought.