diff --git a/Framework/src/CustomParameters.cxx b/Framework/src/CustomParameters.cxx
index d4cb044770..7534379dec 100644
--- a/Framework/src/CustomParameters.cxx
+++ b/Framework/src/CustomParameters.cxx
@@ -202,7 +202,20 @@ void CustomParameters::populateCustomParameters(const boost::property_tree::ptre
   for (const auto& [runtype, subTreeRunType] : tree) {
     for (const auto& [beamtype, subTreeBeamType] : subTreeRunType) {
       for (const auto& [key, value] : subTreeBeamType) {
-        set(key, value.get_value<std::string>(), runtype, beamtype);
+        // Check if value has children (thus it is json)
+        if (value.empty()) { // just a simple value
+          set(key, value.get_value<std::string>(), runtype, beamtype);
+        } else {
+          // It's some json, serialize it to string
+          std::stringstream ss;
+          boost::property_tree::write_json(ss, value, false);
+          std::string jsonString = ss.str();
+          // Remove trailing newline if present
+          if (!jsonString.empty() && jsonString.back() == '\n') {
+            jsonString.pop_back();
+          }
+          set(key, jsonString, runtype, beamtype);
+        }
       }
     }
   }
diff --git a/Framework/test/testCustomParameters.cxx b/Framework/test/testCustomParameters.cxx
index 5d7eccfec7..8389047d9d 100644
--- a/Framework/test/testCustomParameters.cxx
+++ b/Framework/test/testCustomParameters.cxx
@@ -18,8 +18,12 @@
 #include <boost/property_tree/ptree.hpp>
 #include <boost/property_tree/json_parser.hpp>
 #include "getTestDataDirectory.h"
+#include "QualityControl/InfrastructureGenerator.h"
+
 #include <iostream>
 #include <catch_amalgamated.hpp>
+#include <Configuration/ConfigurationFactory.h>
+#include <DataSampling/DataSampling.h>
 
 using namespace o2::quality_control::core;
 using namespace std;
@@ -201,6 +205,35 @@ TEST_CASE("test_load_from_ptree")
   CHECK(cp.at("myOwnKey") == "myOwnValue");
   CHECK(cp.at("myOwnKey1", "PHYSICS") == "myOwnValue1b");
   CHECK(cp.atOptional("asdf").has_value() == false);
+
+  auto value = cp.getOptionalPtree("myOwnKey3");
+  CHECK(value.has_value() == true);
+
+  // Check that it's an array with 1 element
+  std::size_t arraySize = std::distance(value->begin(), value->end());
+  CHECK(arraySize == 1);
+
+  // Get the first (and only) element of the array
+  auto firstElement = value->begin()->second;
+
+  // Check the top-level properties
+  CHECK(firstElement.get<string>("name") == "mean_of_histogram");
+  CHECK(firstElement.get<string>("title") == "Mean trend of the example histogram");
+  CHECK(firstElement.get<string>("graphAxisLabel") == "Mean X:time");
+  CHECK(firstElement.get<string>("graphYRange") == "0:10000");
+
+  // Check the graphs array
+  auto graphs = firstElement.get_child("graphs");
+  std::size_t graphsSize = std::distance(graphs.begin(), graphs.end());
+  CHECK(graphsSize == 1);
+
+  // Check the first graph properties
+  auto firstGraph = graphs.begin()->second;
+  CHECK(firstGraph.get<string>("name") == "mean_trend");
+  CHECK(firstGraph.get<string>("title") == "mean trend");
+  CHECK(firstGraph.get<string>("varexp") == "example.mean:time");
+  CHECK(firstGraph.get<string>("selection") == "");
+  CHECK(firstGraph.get<string>("option") == "*L PLC PMC");
 }
 
 TEST_CASE("test_default_if_not_found_at_optional")
diff --git a/Framework/test/testWorkflow.json b/Framework/test/testWorkflow.json
index e7376eb33f..f02db53386 100644
--- a/Framework/test/testWorkflow.json
+++ b/Framework/test/testWorkflow.json
@@ -28,7 +28,24 @@
           "default": {
             "default": {
               "myOwnKey": "myOwnValue",
-              "myOwnKey2": "myOwnValue2"
+              "myOwnKey2": "myOwnValue2",
+              "myOwnKey3": [
+                {
+                  "name": "mean_of_histogram",
+                  "title": "Mean trend of the example histogram",
+                  "graphAxisLabel": "Mean X:time",
+                  "graphYRange": "0:10000",
+                  "graphs" : [
+                    {
+                      "name": "mean_trend",
+                      "title": "mean trend",
+                      "varexp": "example.mean:time",
+                      "selection": "",
+                      "option": "*L PLC PMC"
+                    }
+                  ]
+                }
+              ]
             }
           },
           "PHYSICS": {