Look no further than Digitalis purpurea when you want to add vertical wow to your garden. These foxgloves reach a height of nearly 5 feet, and their colorful bell-shaped flowers practically scream that spring is full bore. If you missed the window to plant these nifty biennials last fall, don’t despair. Plenty of garden centers will have them on hand this month in pots, just about ready to bloom. Pick up five to seven 1-gallon pots, and group them close together for a show.