diff --git a/src/generic/treectlg.cpp b/src/generic/treectlg.cpp
index 391a1d635d..52868f9226 100644
--- a/src/generic/treectlg.cpp
+++ b/src/generic/treectlg.cpp
@@ -2461,6 +2461,7 @@ int wxGenericTreeCtrl::GetLineHeight(wxGenericTreeItem *item) const
 void wxGenericTreeCtrl::PaintItem(wxGenericTreeItem *item, wxDC& dc)
 {
     item->SetFont(this, dc);
+    item->CalculateSize(this, dc);
 
     wxCoord text_h = item->GetTextHeight();