diff --git a/columnflow/tasks/cmsGhent/plotting.py b/columnflow/tasks/cmsGhent/plotting.py
index 908b322c7..d70cd628a 100644
--- a/columnflow/tasks/cmsGhent/plotting.py
+++ b/columnflow/tasks/cmsGhent/plotting.py
@@ -54,11 +54,12 @@ def run(self):
             for var_name in variable_tuple
         ]
         category_insts = [self.config_inst.get_category(c) for c in self.branch_data.categories]
+        category_insts_leafs = [c.get_leaf_categories() or [c] for c in category_insts]
         process_inst = self.config_inst.get_process(self.branch_data.process)
         sub_process_insts = [sub for sub, _, _ in process_inst.walk_processes(include_self=True)]
 
         # histogram data for process
-        process_hist = 0
+        process_hists = {c.name: 0 for c in category_insts}
 
         with self.publish_step(f"plotting {self.branch_data.variable} for {process_inst.name}"):
             for dataset, inp in self.input().items():
@@ -72,19 +73,12 @@ def run(self):
 
                 # work on a copy
                 h = h_in.copy()
-
-                # axis selections
                 h = h[{
                     "process": [
                         hist.loc(p.id)
                         for p in sub_process_insts
                         if p.id in h.axes["process"]
                     ],
-                    "category": [
-                        hist.loc(c.id)
-                        for c in category_insts
-                        if c.id in h.axes["category"]
-                    ],
                     "shift": [
                         hist.loc(s.id)
                         for s in plot_shifts
@@ -92,28 +86,41 @@ def run(self):
                     ],
                 }]
 
-                # axis reductions
-                h = h[{"process": sum}]
+                # axis selections
+                for c, lcs in zip(category_insts, category_insts_leafs):
+                    hc = h[{
+                        "category": [
+                            hist.loc(c.id)
+                            for c in lcs
+                            if c.id in h.axes["category"]
+                        ],
+                    }]
 
-                # add the histogram
-                process_hist = h + process_hist
+                    # axis reductions
+                    hc = hc[{"category": sum}]
+
+                    # add the histsogram
+                    process_hists[c.name] = hc + process_hists[c.name]
 
             # there should be hists to plot
-            if not process_hist:
+            if not all(process_hists.values()):
                 raise Exception(
                     "no histograms found to plot; possible reasons:\n" +
                     "  - requested variable requires columns that were missing during histogramming\n" +
                     "  - selected --processes did not match any value on the process axis of the input histogram",
                 )
 
-            process_hists = OrderedDict(
-                (cat.name, h[{"category": hist.loc(cat.id)}])
-                for cat in category_insts
-            )
+            # update histograms using custom hooks
+            hists = self.invoke_hist_hooks(process_hists)
+
+            for cat in hists:
+                if "process" in hists[cat].axes.name:
+                    hists[cat] = hists[cat][{"process": sum}]
+
             # call the plot function
             fig, _ = self.call_plot_func(
                 self.plot_function,
-                hists=process_hists,
+                hists=hists,
                 config_inst=self.config_inst,
                 category_inst=process_inst.copy_shallow(),
                 variable_insts=[var_inst.copy_shallow() for var_inst in variable_insts],