property Items.ItemForeColor(Item as HITEM) as Color

Retrieves or sets a foreground color for a specific item.

TypeDescription
Item as HITEM A long expression that indicates the item's handle.
Color A color expression that defines the item's foreground color.

To change the foreground color for a cell call CellForeColor property. To change the foreground color for the entire control call ForeColor property of the control. 

The following sample to change the foreground color for the first column:

Private Sub ExplorerTree1_AddItem(ByVal Group As EXPLORERTREELibCtl.IGroup, ByVal Item As EXPLORERTREELibCtl.HITEM)
    With Group.Items
        .CellForeColor(Item, 0) = vbBlue
    End With
End Sub