diff --git a/sohstationviewer/view/plotting/plotting_widget/plotting_widget.py b/sohstationviewer/view/plotting/plotting_widget/plotting_widget.py
index 80fd5b16ebd2d36ea11369019ccf38065d24ff7f..9bd5fd3d11ceb6cd106724d620e4fd0f6102d60b 100755
--- a/sohstationviewer/view/plotting/plotting_widget/plotting_widget.py
+++ b/sohstationviewer/view/plotting/plotting_widget/plotting_widget.py
@@ -379,8 +379,10 @@ class PlottingWidget(QtWidgets.QScrollArea):
             pass
         self.set_ruler_visibled(self.ruler, xdata)
         if xdata >= self.min_x:
+            ruler_text_content = format_time(xdata, self.parent.date_format,
+                                             'HH:MM:SS')
             self.ruler_text = self.plotting_axes.fig.text(
-                xdata, 75, 'Potato',
+                xdata, 75, ruler_text_content,
                 verticalalignment='top',
                 horizontalalignment='center',
                 transform=self.timestamp_bar_top.transData,