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In the present work, the growth of Eruca sativa L. (rocket plant) on different substrates by addition of biochar in different proportions was studied. The 3 substrates that used are: (soil), (peat & perlite), (biosolids & sand). The biochar that used in this study, is an animal by-product of fur processing which resulted from combustion in a pyrolytic furnace in an anoxic environment with a combustion temperature of 750 - 800 oC and is of 2 species. One species (black) was inactivated in the anoxic furnace for 1 hour and the other (white) inactivated in the anoxic furnace for 12 hours. Thus, on each substrate (Soil, peat & perlite, biosolids & sand) there are three different levels of biochar addition (1:10, 1:2, control) for each biochar species (White and Black). During the experiment, the germination capacity, the height of the above-ground section, the leaf width of the plants, the study of the effect of biochar as a mixture with other fillers were evaluated. The crop of rocket plants is followed by their separation into above ground and underground plant tissue, where the digestion process produces the corresponding solutions (or samples). Finally, the concentrations of heavy metals, macronutrients and micronutrients in both tissue categories (underground and underground) are determined to evaluate the mobility of the constituents and especially the heavy metals from the basement to the underground plant tissue. Measurements were performed using inductively coupled plasma - optical emission spectrometry (ICP OES). From the statistical analysis it was found that in order to achieve the highest height of the above ground part of the plants as well as the largest leaf width of the rocket plants the most appropriate treatment is: White biochar : peat & perlite (1:10). Treating with white biochar : peat & perlite (1:2) has a negative effect on the height of the plants and the width of their leaves. The largest number of rocket plants occurs at the level of white biochar : peat & perlite (1:10) and the level of non-biochar application (control), which are equivalent. Finally, no statistically significant differences were observed in concentrations of macronutrients and micronutrients as well as heavy metals between the underground and underground plant tissue of rocket plants. The only ingredient that is higher in the above ground than in the underground plant tissue is Mg (p-value = 0.030 <0.05).