October is both a time to bring in the last of the harvest and think about the seasons to come. Sue Bradley looks forward to a fragrant summer
They smell great, bring colour and height to the garden and aren’t difficult to grow: sweet peas tick a lot of boxes and October is a good time to start sowing seeds for next summer. This much-loved plant, known as pois de senteur in France, can be grown as annuals or perennials, the latter often sold as ‘everlasting sweet pea’, or Lathyrus latifolius, to call it by its botanical name.
Yet while this climbing plant is prolific when it comes to flowers, its blooms aren’t as fragrant, or available in as many colours, as those of its cousin, L. odoratus.
In fact, there are so many different cultivars of the annual sweet pea from which to choose that one of the hardest things about growing them is deciding which ones to sow.
The oldest available today is ‘Cupani’, which can be traced back to the seeds of a wild plant sent by the Sicilian monk Francis Cupani to various institutions and plant collectors in the late 1690s. Its sweetly scented maroon and violet flower went on to capture the imagination of generations of gardeners, some of whom devoted their lives to developing new cultivars.
Many growers rate members of the Grandiflora group, first developed towards the end of Queen Victoria’s reign and admired for their perfume and elegant flowers. Among their star performers are ‘Prince of Orange’ and the navy blue ‘Lord Nelson’.
Other gardeners, especially those producing blooms for showing, like the frillier Spencer types – bred for the ancestors of Diana, Princess of Wales – which include the cream-flowered ‘Jilly’ and carmine-hued ‘Carlotta’. Sweet peas should be sown in moist compost in containers that provide plenty of space for their long roots. Specialist plastic root trainers are available, although the cardboard tubes from toilet rolls are a good substitute. Sow a couple of seeds per module and keep the developing plants in a cool greenhouse or light, unheated room over winter and allow them to harden off before transferring them to their flowering spot in late spring. Encourage plants to become bushy by pinching out the tips just below a set of leaves. Sweet peas are climbing plants and need some sort of support to keep them off the ground, such as a ‘wigwam’ made from long sticks or pea fencing. Young plants can be tied to their supports when first put into the soil, although in time they should send out tendrils to attach themselves as they develop. Alternatively, look out for some of the new cascading cultivars, such as ‘Sweetie Mix’, that can be grown in hanging baskets. Once sweet peas start producing flowers, it’s important to keep cutting them so that they continue to make more. Remove any emerging seed pods immediately to prevent the plant from thinking its work is done. One of the nicest things about growing sweet peas is that gardeners can easily find homes for posies of these pretty, fragrant flowers if they get too many; a lovely way to cement old friendships and make new ones if ever there was one.