diff --git a/CHANGES.rst b/CHANGES.rst
index 9a57c187..fa6c2d07 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -126,6 +126,9 @@ Changes in this release include the following:
 
 * Performance update for `wx.lib.agw.customtreectrl` (#1049)
 
+* Ensure that colours set in wx.lib.agw.customtreectrl.TreeItemAttr are
+  instances of wx.Colour. (#1032)
+
 * Fix drawing of ticks in wx.lib.agw.speedmeter when there are negative bounds
   values. (#1013)
 
diff --git a/wx/lib/agw/customtreectrl.py b/wx/lib/agw/customtreectrl.py
index 70a356fb..94f13b81 100644
--- a/wx/lib/agw/customtreectrl.py
+++ b/wx/lib/agw/customtreectrl.py
@@ -857,7 +857,7 @@ class TreeItemAttr(object):
         :param `colText`: an instance of :class:`wx.Colour`.
         """
 
-        self._colText = colText
+        self._colText = wx.Colour(colText)
 
 
     def SetBackgroundColour(self, colBack):
@@ -867,7 +867,7 @@ class TreeItemAttr(object):
         :param `colBack`: an instance of :class:`wx.Colour`.
         """
 
-        self._colBack = colBack
+        self._colBack = wx.Colour(colBack)
 
 
     def SetBorderColour(self, colBorder):
@@ -879,7 +879,7 @@ class TreeItemAttr(object):
         .. versionadded:: 0.9.6
         """
 
-        self._colBorder = colBorder
+        self._colBorder = wx.Colour(colBorder)
 
 
     def SetFont(self, font):
diff --git a/wx/lib/agw/hypertreelist.py b/wx/lib/agw/hypertreelist.py
index ce008d11..7ce30988 100644
--- a/wx/lib/agw/hypertreelist.py
+++ b/wx/lib/agw/hypertreelist.py
@@ -2366,7 +2366,7 @@ class TreeListMainWindow(CustomTreeCtrl):
 # operations
 # ----------------------------------------------------------------------------
 
-    def DoInsertItem(self, parent, previous, text, ct_type=0, wnd=None, image=-1, selImage=-1, data=None, separator=False):
+    def DoInsertItem(self, parent, previous, text, ct_type=0, wnd=None, image=-1, selImage=-1, data=None, *ignored_args):
         """
         Actually inserts an item in the tree.
 
@@ -2383,7 +2383,7 @@ class TreeListMainWindow(CustomTreeCtrl):
          use for the item in selected state; if `image` > -1 and `selImage` is -1, the
          same image is used for both selected and unselected items;
         :param `data`: associate the given Python object `data` with the item.
-        :param `separator`: unused at the moment, this parameter is present to comply with
+        :param `ignored_args`: unused at the moment, this parameter is present to comply with
          :meth:`CustomTreeCtrl.DoInsertItem() <lib.agw.customtreectrl.CustomTreeCtrl.DoInsertItem>` changed API.
         """