diff --git a/haystack_experimental/components/splitters/hierarchical_doc_splitter.py b/haystack_experimental/components/splitters/hierarchical_doc_splitter.py
index 32366f6a..d6248226 100644
--- a/haystack_experimental/components/splitters/hierarchical_doc_splitter.py
+++ b/haystack_experimental/components/splitters/hierarchical_doc_splitter.py
@@ -72,6 +72,7 @@ def _build_block_sizes(self):
             self.splitters[block_size] = DocumentSplitter(
                 split_length=block_size, split_overlap=self.split_overlap, split_by=self.split_by
             )
+            self.splitters[block_size].warm_up()
 
     @staticmethod
     def _add_meta_data(document: Document):