SWEET peas are plants I grow every year – their smell, colour, memories of childhood all play a part in this quintessentially English cottage garden flower.
Of course, the ability to sow them as early as January is a big pull, as most of us are itching to kick start the new season.
Most popular are the tall (180cm/6ft), frilly Spencer types, although there are plenty of dwarf varieties on the market now.
This year, I’ve ended up with eight packets (two identical) – a collection of six, plus one in an annual climbers collection, both from Mr Fothergill’s, plus a free packet with Gardeners’ World magazine. I’ll be giving plenty away!
Scent is the big draw for most – there’s nothing so disappointing than a sweet pea with no smell.
And don’t be fooled by the name – sweet peas are poisonous.
There are many rituals surrounding sweet pea seeds. Some people swear by soaking them overnight to soften the case; others file a spot on the seed.
I don’t do either of these and have always had a good germination rate, as long as the soil is moist and the temperature constant.
Sow indoors, January-March or September-October, 1.5cm (½”) deep, either five seeds per 12cm (5”) pot of compost, or I find 3-4 seeds in a family-sized yoghurt pot works well, as they like a deep root run.
Water well and place in a greenhouse, cool windowsill or thermostatically-controlled propagator at a temperature of 15°C (60°F).
Keep the pots moist, germination usually occurs in 12-21 days. Once through, make sure the seedlings have good light, to avoid weak, leggy growth.
Pinch out the growing tip, when two pairs of leaves have formed, to encourage bushy growth.
Gradually harden plants off before planting out into well-drained soil, April-May, 30cm (12”) apart and support with tall canes or netting. Protect from frost.
You can sow directly outdoors in April-May, where they are to flower, 1.5cm (½”) deep. Sow two seeds together, every 30cm (12”), then remove the weaker. Easier, but the flowers are much later.
You can also sow in pots in September/October, for much earlier flowering, but they need to be overwintered in cool, but frost-free conditions.
SOWING TIME: September/October or January-March under glass; April/May outside where to flower.
FLOWERING TIME: May-October. Pick blooms regularly to prolong the flowering season.
PLANTING DISTANCE: 30cm (12”) apart.
ASPECT AND SOIL: Full sun, well-drained. If your soil is acidic, lime before planting.
DIFFICULTY: Easy. Protect seedlings against bird damage with short twigs.
Sweet pea history
ALTHOUGH seen as an English cottage garden plant, sweet peas most probably came from Sicily, or Malta.
Francisco Cupani recorded it as being a new plant on Sicily in 1695. He was charged with the care of the botanical garden in Misilmeri, near Palermo.
British botanist Dr Robert Uvedale introduced the sweet pea in his garden, with a herbarium specimen from 1700 surviving, now in the Natural History Museum.
Both men have varieties named after them - Cupani is a grandiflora heritage variety, very similar to the old plant, with very strongly-scented small bicolour flowers.
In contrast, Robert Uvedale only made its debut in 2014, bright pink with large frilly blooms.
Silas Cole, a gardener working for the Spencer family (of Diana, Princess of Wales fame), bred a plant with bigger flowers and a wavy petal edge in 1900. It was bright pink and named Countess Spencer, the first of many ‘Spencer’ introductions.