TextBox box = new TextBox();
box.Multiline = true;
box.Text = "Some random text here...";
box.BorderStyle = BorderStyle.None;
gridControl1.RowHeights[2] = 30;
gridControl1.ColWidths[2] = 200;
gridControl1[2,2].CellType = "Control";
gridControl1[2,2].Control = box;
this.Controls.Add(box);