Annual sweet pea comes from the Mediterranean and has been refined by breeders for centuries into hundreds of cultivars spanning nearly every color except true yellow. The dark green leaflet pairs and winged stems end in tendrils that will grip any available support, reaching 8 feet as a climber or staying to a compact 3-foot bush if grown without a structure. The flowers are the point: ruffled, intensely fragrant, and produced in generous succession so long as the weather stays cool and spent flowers are removed before they set seed.

This is emphatically a cool-season annual. In most of North Carolina and the wider South, that means a spring planting as early as possible and an acceptance that summer heat will end the show. Plant seeds in rich, fertile, well-drained soil with organic matter and consistent moisture, and mulch to keep the roots cool. Sweet pea and edible peas should never share a bed since the ornamental is toxic. Heat-tolerant cultivars exist but the fragrant old varieties are generally the most rewarding, and those tend to be the most temperature-sensitive.