changing headertext of columns dynamically in gridview

I am using the following code in Row created event, but this is not working. The grid view has also sorting enabled

protected void grdProducts_RowCreated(object sender, GridViewRowEventArgs e)

{

GridViewRow row = e.Row;

if (e.Row.RowType == DataControlRowType.Header)

{

row.Cells.Text = ViewState["col1"].ToString();

}

}

Why cannot you use the GridViewColumn's HeaderText property?

this.resultGrid.Columns[0].HeaderText = "whatever";