Fertile soil - these two words have certainly caught the ear of every one of us, even if we have nothing to do with farming or gardening on a daily basis. But do we really know what fertile soil actually is? Without a doubt, soil that provides the most favourable conditions for plant growth - warmth, water, air and essential nutrients - deserves the name. However, it is worth knowing that these are difficult to achieve, as they depend on many factors. 

The most important factors affecting soil fertility are the humus content and the moisture, temperature and air content of the soil. 

Fertile soil is therefore rich in humus. Humus is the second layer of soil and is formed from the decomposition of plant and animal remains. It is in it that compounds are contained, without which plant growth would not be possible. Between its clods are spaces where water and air are stored and used by soil organisms and plants. 

Interestingly, soil fertility is not expressed in numbers, it is essentially immeasurable. It is evidenced by the ability to grow more demanding crops in a given area, the size and quality of the crop, or the amount of biomass produced. 

In Poland, the most fertile soil is considered to be chernozem, which accounts for about 1 per cent of the country's area. Chernozem can be found in the Lublin Upland, the Małopolska Upland and the Głubczycki Plateau. Equally fertile soil is black earth, which also accounts for around 1 per cent of the country's area. They are mainly found in the Kujawy region, but can also be found in the Wielkopolska, Szczecin and Silesian Lowlands.   

However, it is worth mentioning that humans can contribute to making the soil fertile. There are several ways that can be applied even in one's own garden. Well, organic fertilisers are effective in improving the soil. The soil can be enriched with compost, manure, peat, biohumus, manure or catch crops. Interestingly, each of us can easily create our own compost pile from which to draw compost for the garden. 

Fertile soil, is particularly important for farmers who harvest their crops every year. They in particular take care to ensure that the soil is fertile. They are therefore no strangers to the use of fertilisers, the application of crop rotation or the well thought-out drainage of the field. It may come as a surprise to many, but it turns out that straw is an effective organic fertiliser, helping to maintain humus levels in the soil. 

Fertile soil on which a bountiful harvest grows is important for garden owners and farmers alike. A red ripe strawberry is as much a delight for the experienced grower as for the city dweller. Therefore, in the face of changing climatic conditions, it is important to take care of the quality of the soil that future generations will use.