Numerous studies show a positive effect of fungal colonization to higher plants. The positive effects are a better uptake of nutrients, better resistance to water stress, increased crop production and better resistance to diseases. The researches so far have been carried out under controlled conditions. Therefore, the purpose of our task was to check the status of minerals in the soil of the fields in Slovenia. For the survey we selected organic farms spread across Slovenia. Samples were collected from six regions: Primorska, Notranjska, Gorenjska, Dolenjska, Štajerska and Prekmurje. The samples of wheat were collected in summer 2014 while the samples of buckwheat were collected in the autumn of the same year. Samples were always collected in the same way. We wanted to find out what is the type of the fungal colonization of wheat and buckwheat and measure the selected soil characteristics (pH, organic matter content, plant available phosphorus concentration) and the concentration of minerals (Zn, Cu and Fe) in the soil and in the seeds. Fungal colonization was observed in the roots of both species. In wheat we could observe structures of arbuscular mycorrhizal fungi, as well as structures that are typical of dark septate endophytes. Buckwheat was largely colonized only by dark septate endophytes. Fields were well supplied with organic matter and phosphorous. The concentration of minerals in the soil and in the seeds is comparable with the previously published data. The measured pH was slightly higher than the value of the last measurements in the upper layer of the soil in Slovenia.