A fermentation plant for biological material having the following characteristics: - a fermentation container for receiving biological material having an evenly formed container bottom having a linear bottom contour running rectangular to two container side walls (11, 12) being parallel to each other, wherein the fermentation container is formed in an extended manner along a container extension axis, - a plurality of same agitators respectively arranged around an agitator rotation axis in a rotatable manner and intended for agitating received biological material, wherein the agitators are arranged consecutively along the container extension axis in an agitator-rotation-distance, wherein the agitators have at least one first agitator bar and a second agitator bar respectively fixed in the region of the agitator rotation axis, and the agitator rotation axes are arranged vertically to the container extension axis, wherein the fermentation container has along the agitator rotation axis cut in the direction of the container bottom a cross-sectional contour with the two container side walls (11, 12) running parallel to each other and being arranged vertically to the agitator rotation axes and between which the container bottom extends with the straight bottom contour adjacent downwards the fermentation container, - wherein the first agitator bar and the second agitator bar each have at least a bottom section (212, 222), wherein the bottom sections (212, 222) extend parallel to the agitator rotation axis and each are spaced apart from the agitator rotation axis such that the bottom sections (212, 222) upon rotation of the agitator sweep past just above the container bottom, wherein the agitator-rotation axis-distance is less than 1.5 times, preferably less than 1.2 times the maximum distance between the agitator rotation axis and the container bottom, characterized in that the first agitator bar and the second agitator bar each starting from a first rotation axis mounting section in the region of the agitator rotation axis through a reversal region spaced apart from the agitator rotation axis run back in the direction of agitator rotation axis such that the agitator bars (21, 22) grasp through the biological material being in the fermentation container not only on the way starting from the agitator rotation axis to the reversal region but additionally also in further regions arranged between the reversal region and the agitator rotation axis and that the first agitator bar and the second agitator bar have seen along the agitator rotation axis bottom sections (212, 222) arranged in an alternating manner relative to each other. - a fermentation container for receiving biological material having an evenly formed container bottom having a linear bottom contour running rectangular to two container side walls (11, 12) being parallel to each other, wherein the fermentation container is formed in an extended manner along a container extension axis, - a plurality of same agitators respectively arranged around an agitator rotation axis in a rotatable manner and intended for agitating received biological material, wherein the agitators are arranged consecutively along the container extension axis in an agitator-rotation-distance, wherein the agitators have at least one first agitator bar and a second agitator bar respectively fixed in the region of the agitator rotation axis, and the agitator rotation axes are arranged vertically to the container extension axis, wherein the fermentation container has along the agitator rotation axis cut in the direction of the container bottom a cross-sectional contour with the two container side walls (11, 12) running parallel to each other and being arranged vertically to the agitator rotation axes and between which the container bottom extends with the straight bottom contour adjacent downwards the fermentation container, - wherein the first agitator bar and the second agitator bar each have at least a bottom section (212, 222), wherein the bottom sections (212, 222) extend parallel to the agitator rotation axis and each are spaced apart from the agitator rotation axis such that the bottom sections (212, 222) upon rotation of the agitator sweep past just above the container bottom, wherein the agitator-rotation axis-distance is less than 1.5 times, preferably less than 1.2 times the maximum distance between the agitator rotation axis and the container bottom,