We’ve added this functionality recently, so with next hotfix you will be able to achieve this with:

this.ultraChart1.ColumnChart.ChartTextValueAlignment = ValueAlignment.PositiveAndNegative;

For now as workaround you can try removing the column labels and adding them manually with:

this.ultraChart1.FillSceneGraph += new Infragistics.UltraChart.Shared.Events.FillSceneGraphEventHandler(ultraChart1_FillSceneGraph);

…

  void ultraChart1_FillSceneGraph(object sender, Infragistics.UltraChart.Shared.Events.FillSceneGraphEventArgs e)

        {

            // first get a reference to all the columns/bars in the chart.

            ArrayList allBoxes = new ArrayList();

            foreach (Primitive p in e.SceneGraph)

            {

                // Loop through each (box) primitive and load the boxes with non-null non-zero data.

                Box b = p as Box;

                if (b != null)

                {

                    // exclude the chart area (which are also boxes but not part of the data chart)

                    if (b.rect.X != 0 && b.rect.Y != 0)

                    {

                        allBoxes.Add(p);

                    }

                }

            }

            // These boxes represent the chart data

            foreach (Box b in allBoxes)

            {

                if (b.Value == null)

                {

                    continue;

                }

                double boxValue = Convert.ToDouble(b.Value);

                LabelStyle labelStyle = new LabelStyle();

                SizeF labelSize = Infragistics.UltraChart.Core.Util.Platform.GetLabelSizePixels(b.Value.ToString(), labelStyle);

                // Add a text or the column value on top or on bottom of each column.

                int x = b.rect.X + b.rect.Width / 2 - (int)(labelSize.Width / 2);

                int y;

                int labelOffset = 2;

                if (boxValue >= 0)

                {

                    y = b.rect.Y - (int)labelSize.Height / 2 - labelOffset;

                }

                else

                {

                    y = b.rect.Bottom + (int)labelSize.Height / 2 + labelOffset;

                }

                Point textPoint = new Point(x, y);

                // Create a text object to be displayed on the column (string column value can be used).

                Text txtColumn = new Text(textPoint, b.Value.ToString(), labelStyle);

                // Add the customized text to the chart.

                e.SceneGraph.Add(txtColumn);

            }

        }