All forms of cultivation require high-quality soil. Crop yields will not be good if the soil is not well managed, limed, drained, loose and sufficiently rich in organic matter. Soil characteristics affect the cultivation method, the erosion risk of the parcel, nutrient leaching risk, fertilisation and lime requirements, risk of compaction and the level of greenhouse gas emissions.
Coarse mineral soils and organic soil types are common in Finland. One third of the fields contain clay soil types. The clay soils concentrate in Southwest Finland. The share of peatland in the arable land areas of Lapland, Northern Ostrobothnia and Kainuu is 20–40%. A quarter of arable land in Ostrobothnia and Southern Ostrobothnia consists of organic soil types.
The pH levels of topsoil acidity are naturally low everywhere in Finland, meaning that Finnish soil is acid. Most crop varieties thrive best in neutral and slightly acid soil. Soil acidity can be reduced by adding lime. The use of soil improvement lime has declined in recent decades.
A low nutrient content is typical of Finnish arable land. To grow, plants need a balanced intake of nutrients. There are great variations between the trace element contents of arable soil in different areas, and the status of trace elements in arable soil has been observed to deteriorate. Soil fertility studies indicate that in Finland the levels of highly soluble harmful heavy metals, such as cadmium, lead, chromium and nickel, are low by international comparison.