The wonderful garden plant (Campanula persicifolia) is known to have been in cultivation since the mid-16th century. A perennial, its delicate beauty belies its toughness. it blooms from spring till frost, grows in sun or shade, and is both heat- and drought-tolerant. The blooms are an inch or better wide on stems that can rise to 24 inches and the plant spreads to two inches wide. A winner in every way.