Brown and luvisols soils – occupy slightly more than half of all soils. Depending on the parent rock, they are classified as quality class III and IV (substrate consisting of sand), and less frequently as class II (clayey substratum).
Podzolic soils – occupying approximately 25% of the country's area, these soils consist of sandy and gravel substrates and are currently classified as classes V and VI.
Chernozems – occupying 1% of the country, these soils have a loess substrate rich in calcium and magnesium. They were formed by supplying abundant organic matter to the substrate, primarily in areas densely covered with grasses. Consequently, they feature a deep humus layer with a high content of calcium and magnesium cations, making them the most fertile soils.
Black soils – their base consists of clay, silt, and dusty formations enriched with lime, which were formerly marshy areas. Currently, these are flat, low-lying regions, constituting approximately 1% of the country's area. They are highly fertile, akin to chernozems.
Alluvial soils – constitute 5% of our soils. Formed by the deposition of material by rivers. Characterized by a layered profile with various horizontal areas of different composition. Among the most fertile Polish soils.
Rendzina – they are fertile and constitute approximately 1% of our soils. Formed on limestone rocks, they are saturated with calcium and magnesium. Their soil profile is shallow, contains a significant amount of gravel and stones, making them challenging to cultivate (hence classified as classes III–V) and simultaneously susceptible to erosion.

The most common Luvisols in our country can have a sandy or clayey substrate. Therefore, they are classified as very light to medium soils, respectively. A clayey substrate guarantees better storage of rainwater and its infiltration into the topsoil. If Luvisols have a sandy substrate, it will not store water, which is currently the biggest problem of such sites. The topsoil itself of such lands also has limited water retention capacity due to the dominance of large pores, the so-called macropores (see Chapter 1e - Soil water capacity).

What is a soil profile and its structure
Soil profile a vertical cross-section of soil reveals its morphology, or structure. It can be divided into horizontally arranged genetic horizons, which differ in mineral composition, humus content, structure, and color. For a farmer, the most important are the organic horizon and the humus horizon, the two top layers of soil containing organic matter and humus. In the cross-section, these horizons are usually dark in color, and the darker they are, the more organic matter and humus they contain.

A properly constructed soil profile is 1.5 meters deep, allowing for comprehensive determination of physical features, such as soil condition, depth of topsoil, subsoil condition, and disturbances in soil structure, including compaction and the plough sole. The photo above depicts class IVb lessive soil with a distinct separation between the humus (topsoil) layer and the sandy layer. This indicates that the soil requires systematic addition of organic matter to increase its water capacity and improve its structure. The limited subsoil on this plot affects the soil's ability to retain water.

Terminology
Bonitation class – a soil quality class determined within the framework of soil classification based on an official soil table, indicating the quality of soil in terms of its utility value.
Loess soils - originate from the top layer of loess. Their composition renders them notably fertile, requiring minimal fertilization, and they retain water efficiently while maintaining a favorable water-air ratio.
The humus level – ideally, it should be around 5% in fertile arable soil, while most soils in Poland have a humus content of 1.5-2%, with some soils having even 0.5% content.