The sweet pea, Lathyrus odoratus, is an annual climbing flower cherished globally for its delicate beauty and powerful fragrance. Gardeners and florists prize this plant for its long vase life and wide array of colors, making it a favorite for cottage gardens and bouquets. Before widespread cultivation, the sweet pea existed as a humble wildflower. Its transformation from a small wild vine to a highly sought-after ornamental plant involved global botanical exchange and focused breeding efforts.
The Wild Origins of Sweet Peas
The geographic home of the sweet pea is the Mediterranean region, specifically Sicily, parts of southern Italy, and the Aegean Islands. The plant thrives in this climate, which features cool, moist winters and hot, dry summers, favoring its annual growth cycle. In its native habitat, the wild form of Lathyrus odoratus is a relatively unassuming climber, distinct from the showy flowers grown today.
The original wild sweet pea, often called the ‘Cupani’ type, was smaller and less floriferous than modern varieties. It typically featured only two flowers per stem and displayed a deep, bicolored purple and maroon coloration. Despite its modest size, this ancestral form possessed an intensely sweet perfume, a defining characteristic of the species. This native form continues to inspire breeders even after centuries of intensive cultivation.
The Journey from Wildflower to Garden Favorite
The sweet pea’s journey into cultivation began in the late 17th century. Franciscan monk Father Franciscus Cupani recorded the plant while writing a flora of Sicily, first mentioning it around 1696. He sent seeds from Sicily to botanists and collectors across Europe. The seeds were introduced to England shortly after, where enthusiasts like Robert Uvedale grew them in Enfield.
For over a century, the plant remained largely unchanged in cultivation, with only a few color variants appearing, such as white, scarlet, and the bicolored ‘Painted Lady.’ The major shift began in the late 19th century with the work of Scottish gardener Henry Eckford. Eckford’s selective breeding focused on creating larger flowers, longer stems, and a broader color range, resulting in the group known as Grandifloras.
Understanding Modern Sweet Pea Varieties
Modern sweet peas are broadly classified into two main groups, each representing a different stage in the plant’s breeding history. The Grandiflora varieties trace their lineage directly to Eckford’s early work. They are known for their strong, traditional scent and plain, non-ruffled petals. These types have a flower size and stem length intermediate between the original wild form and the later, highly hybridized types.
The second and most popular classification is the Spencer type, which emerged from a natural mutation in 1901 and was named after ‘Countess Spencer.’ Spencer sweet peas are distinguished by their large, ruffled or wavy petals, long stems, and the widest available color range. The trade-off for this dramatic increase in size and visual complexity is often a decrease in the intensity of the famous fragrance. Breeders continue to develop new varieties, sometimes combining the large size of Spencers with the robust scent of Grandifloras in types called Modern Grandifloras.