Perennials or more technically,
herbaceous perennials are plants
that live more than two years (to distinguish them from
biennials) and whose foliage dies back to the ground with the
frost in autumn or because of a dry season. They survive as
either roots, crowns or other structures beneath the soil
surface during the dormant period. Then, usually in the spring
or when the conditions are right for new growth, they will
emerge from the ground for another cycle.
Here are the common genera of herbaceous perennials found in
home landscapes in the temperate zones of North America: