Whether a plant is useful for insects depends wholly on the accessibility of its flowers (be it for nectar or pollen). Insects prefer the more open, singleflowered or semi-double varieties but can make little use of the tightlypacked, fully double blossoms of our cultivars. Although we planted most of our perennials following this insect- friendly guideline, a few exceptions snuck into our borders, as some of these flowers are simply too dear to our hearts for us to go without them.