Rhubarb

A giant herbaceous perennial from Southeast Asia and the principal wild ancestor of most cultivated dessert bananas. What looks like a trunk is a 'pseudostem' - tightly rolled leaf sheaths - topped by a fountain of huge, paddle-shaped leaves that can run 6 to 10 feet long, giving an instant tropical effect. In frost-free climates (USDA zones 10a-11b) an established clump produces a drooping flower spike and a hanging bunch of edible fruit, then that pseudostem dies and is replaced by a sucker from the base. It is frost-tender: everywhere colder it is grown as a bold container or greenhouse foliage plant that is overwintered indoors and rarely, if ever, fruits.

A fast, suckering native shrub of streambanks and moist thickets across eastern North America, grown for huge flat-topped cymes of tiny lemon-scented white flowers in early summer and the clusters of dark elderberry drupes that follow. Spreads by root suckers into naturalized colonies 5 to 12 feet tall and wide; the flowers feed butterflies and the showy fruit feeds birds. The raw berries are not eaten fresh - they are cooked into jelly, pie, and wine.

A Mediterranean thistle relative grown as a perennial vegetable for its large, unopened flower bud - the edible "globe" of overlapping fleshy bracts harvested before bloom. It forms an upright clump of deeply lobed, jagged silver-green leaves, with flower stalks rising to 3 to 5 feet. Left unharvested, the buds open to spectacular violet-blue thistle flowers up to 7 inches across that are a magnet for bees.

A clumping, multi-stemmed evergreen perennial from South Africa, grown for its unmistakable crane-head flowers - a horizontal green-and-pink spathe from which bright orange sepals and vivid blue petals emerge like the crest of an exotic bird. Bold, paddle-shaped blue-green leaves on long stalks form a 3-4 foot fountain of foliage. Winter hardy only in USDA zones 10-12 (frost-free subtropics); everywhere colder it is grown as a houseplant or summered-out container plant. It blooms reliably only from a well-established, somewhat crowded clump, so patience is the key to flowers.

A long-lived native perennial of central and eastern US woodland borders and prairie meadows with deep blue pea-shaped flowers in late spring, blue-green leguminous foliage, attractive black seed pods for winter interest, and a nitrogen-fixing root system (Fabaceae). Larval host for 6 documented butterfly species per NC State (orange sulphur, clouded sulphur, frosted elfin, eastern tailed-blue, hoary edge, wild indigo duskywing) - among the highest Lep-host-count perennials in the eastern flora.

A bold, moisture-loving native perennial of eastern North America that dies back to a woody base each winter and returns to throw up stout 2 to 6 feet stems topped with enormous 4-8 inch saucer-shaped flowers - white, pink, red, or burgundy, each with a contrasting central eye - from June into September. NC State Extension describes a herbaceous perennial hardy across USDA zones 4a-9b that thrives in wet to constantly moist soils, tolerates heat, humidity, and even brief flooding, and draws hummingbirds, butterflies, and other pollinators. The tropical-looking dinner-plate blooms make it a dramatic focal point for rain gardens, pond edges, and the back of a sunny border.