It’s hard to believe that the frilly, colourful and fragrant vines of sweet pea flowers were once the subject of intense scientific scrutiny. Yet, much of what is known about genetics today can be traced back to mid-nineteenth century studies of Lathyrus odoratus.
Sweet peas were sought after by natural scientists because they are self-pollinating annual flowering plants and the measurable genetic traits of colour, height and petal form were easily observable. Pioneer geneticist, Reginald Punnett, published a paper on genetic linking of sweet peas and led the way to establishing the new field of study, ‚”genetics”, at Cambridge University.
But sweet peas had been a garden favorite many years before their role in the science lab. Near the end of the 17th century, botanist Father Francis Cupani found the fragrant flowering vines growing wild in the mountains of Sicily. He sent them back to England were their bright colours and intoxicating fragrance soon earned them a place in almost every garden.
As self-pollinators, sweet peas are easy to breed and hybridize. Today the gardener looking for bright colour and sweet fragrance in the spring garden can choose from among a vast number of cultivars.
Sweet peas are an annual climbing flowering vine that can grow five to nine feet long. The small oblong pinnate leaves support a tendril that helps the plant climb by twining itself around plants, fences or any other support it can reach. Dwarf varieties grow between eight and 20 inches high.
Sweet peas are suitable for growing in containers where the vines can hang or be encouraged to climb and cover a centre support.
They prefer a cool climate, but will do well in hotter zones provided they are kept well watered. Mulching around the roots after the vines have grown will help keep the roots cool and moist.
Sweet peas do not transplant well, but can be easily grown from seed sown directly in the garden or container. Seeds should be soaked overnight before planting. Space seeds 3-4 inches apart in a rich well-drained soil as soon as the ground can be worked in spring and where the vines will receive full sun. Water the newly planted seeds well, but restrict further watering until the seeds germinate in about a week, then water regularly.
Like all members of the legume family, sweet peas absorb nitrogen from the air and fix it in their roots. This means that they need little in the way of fertilizers while growing. Over-fertilizing sweet peas will cause leaf growth at the expense of flowers.
When the vines have reached 3-6 inches, pinch them back gently to encourage bushiness and more flowers. The vines should begin flowering 6-8 weeks after germination.
Sweet pea flowers come in nearly every colour except yellow. The flower bunches can be cut for colourful and fragrant spring flower arrangements. Deadhead the vines regularly to encourage more flowers, but flowering will slow and stop when the weather grows hot.
Be sure to leave some flowers on the vine to develop seeds that can be stored for next year’s crop.
Sources
Canadian Gardening
National Sweet Pea Society
Most homeowners have probably spent hours looking at the different types of garden seeders. You may have even come across…
When it comes to vehicle lovers, cleaning their cars on a regular basis is essential to maintaining the paint job's…
Gas chainsaws are the perfect tool for a variety of outdoor tasks, including chopping up logs for firewood, clearing brush…
A home can be a daunting project, one that takes some time and energy to maintain. With hard work, determination,…
Today ginger is grown all over tropical and subtropical regions in Asia, in parts of Africa and South America, and…
Onions are one of the most popular vegetables in the world, and growing onions is a snap in the home…