When I grow sweet peas (Lathyrus odoratus), I’m not demanding about their colour or form — scent is my first priority. I wouldn’t grow them if they didn’t have a lovely fragrance. Much has been written about the superior scent found in older sweet peas like purple-red ‘Matucana’ (Veseys.com), grown since about 1700, and reputed to be more intensely perfumed than modern varieties. I’ve been sleuthing around in catalogues, carefully reading the descriptions, and trying to find out what’s going on with sweet pea perfume.
What I notice is that a lot of breeding efforts have produced sweet peas of various heights, enlarged flower sizes, deeply rippled petal forms and complex colours. Scent is still a basic component of all sweet peas, although the intensity of fragrance is inconsistent from one flower to another. Some varieties are described as being lightly or softly scented, while others threaten to knock your socks off with perfume. It may be that the scent genes are plentiful and present to some extent in every sweet pea flower, but plant breeders seem to have left the scent genes alone, presuming that whatever perfume a flower offers is satisfactory.
Well, yes, any amount of scent is a good thing in sweet peas, but some sweet peas are more deeply scented than others, and those are the ones I want to grow. While searching for those with the most intense fragrance, I’ve come across individual named sweet peas and mixed collections that seem to promise strongest perfume.
‘Old Spice’ is a familiar collection of modern mixed colours (scarlet, deep purple, pink and rose) with strong scent, and the added benefit of heat resistance. When other sweet peas are burned out by summer sun, ‘Old Spice’ will keep going. ‘King’s High Scent’ (syn. ‘High Scent’, ‘Hi-Scent’) has large cream flowers edged with pale violet, and deeply perfumed petals. ‘Fragrantissima’ is a mix of deeply ruffled flowers in complementary shades of white, pink, red, blue and purple, with striped and bi-coloured flowers. These three are all from territorialseed.com.
‘Scent Infusion’ is a mix of highly scented modern vines, and the individual components of the mix are ‘Heathcliff’, ‘Memories’, ‘April in Paris’, ‘Albutt Blue’ and ‘Fire and Ice’. ‘Elegant Ladies’ is a mixed collection of heirloom sweet peas with the strong scent, including ‘Cupani’, ‘Miss Wilmott’, ‘Painted Lady’, ‘Sicilian Fuchsia’ and ‘Countess Cadogen’. These mixed collections are from thompsonmorgan.ca.
‘Incense Mix’ (Stokeseeds.com) is a pastel group of pink, white and white with violet flowers claiming to be the most fragrant cutting varieties.
Sweet pea vines grow in cool spring temperatures and can be sown outdoors as soon as the soil is drained and workable. They require a trellis or other means of support, and are good vines for container growing. They reach a height of four to six feet (1.2 to 1.8 m), and need consistent moisture. Heat and dry soil cause the vines to stop flowering, but if you’re growing ‘Old Spice’, you might keep it going into midsummer.