Let me count the ways…
Well, for a start the scent is hands-down THE BEST. There’s no competition - as far as I’m concerned - for the rich, intoxicating perfume of sweet peas in full flower, warmed by the sun. Caught on a summer breeze it’s enough to make you immediately put down your G&T and head straight over to bury your face in a luxurious handful of those soft, velvety blooms.
But that’s not all. Sweet peas are brilliantly colourful and available in hundreds of cultivars, from pure white through palest pink to violet, crimson, deep claret and almost black. Some 50 of these have the coveted Award of Garden Merit from the Royal Horticultural Society.
They’re also fast-growing and tall, so make a fantastic ‘green screen’, tepee or scented archway (my favourite kind of garden structure). They’re also debatably the greatest cut flower ever: just four or five stems are enough to scent a whole room. And if that weren’t enough, the more you cut, the more they flower.
Here I’m talking of the annual sweet pea, Lathurus odoratus. But I love the perennial version, Lathyrus latifolius (which comes in magenta, soft blush-pink or white) too, and it certainly has its place in the garden, scrambling up a fence in a sunny spot. And although the shape of the flowers is gorgeous – the white ones remind me of a climbing lily of the valley – I miss that unmistakable sweet pea scent.
I grew up with sweet peas. My mum sowed them every year in our Shropshire garden. She’d plant them both in her flower borders and in the veg patch, where they attract pollinators that also go to work on climbing beans. They seemed to do well there, growing tall and sturdy without much attention. Or is it just that I didn’t notice the attention she gave them?
Either way, my London sowings have always been slightly disappointing – straggly or stunted, or barely taking off at all. It’s probably the heavy clay soil. If you’re sowing from seed (the advantage being you’ll be able to choose from a much wider variety of cultivars), here are the basics for sweet pea success:
- Sow seeds in a cold frame or greenhouse, in February or March (you can do this in autumn too).
- Use sharp-draining gritty compost and, ideally, sow into root-training modules. Sweet peas don’t like their roots to be disturbed. Modules unclip to open up, so transplanting them into their final spot means you won’t upset those sensitive roots. If you sow now, your plants will flower from mid-June to September.
- If you want to go straight into the ground, sow seeds about 10 cm apart at the foot of trellis or canes. N.B. This is a much less reliable method, as your seeds are at the mercy of cold, wet and/or digging pests (squirrels and foxes, I’m looking at you…)
- Harden off your plants really well. If you don’t, they can sulk and fail to get going for a long while. In practice, this means accustoming them to outside temperatures by bringing them out of the cold frame/greenhouse at first for a couple of hours a day in spring, then for whole days before returning them to safety at night. Do this over a period of 2-3 weeks before planting out time, which is once there’s zero danger of frosts – so early to mid-May in the south, late May or even June further north.
However, last spring I swallowed my sweet pea pride and decided to cheat (it seemed like an enormously guilty, lazy act, for which I would be punished roundly by the gardening gods) and ordered root-trained seedlings from Ashridge Nurseries. Anniversary, Mrs Collier and Noel Sutton. My brilliant little seedlings arrived in early May and after a few days hardening them off outside, I planted them carefully in their final spots, making sure the planting holes were roomy and tucking them in a little deeper than they had been in their root trainers.
Ashridge Nurseries grown sweet pea seedling and root plug
One group I grew up a black painted steel obelisk, the others around a simple cane wigwam in one of my square vegetable beds, with lettuces and herbs filling the empty corners. I really should have given them a high-potash feed every couple of weeks, but I’m a forgetful (and busy) gardener so that didn’t happen. I did fork some garden compost through the soil before planting, though, and that was enough for good strong plants that shot off up their supports and gave me amazing scented flowers until the end of September at least.
Noel Sutton gets going in mid-May
I’m now a convert. This year I’m planning on more sweet peas, root-trained again for obvious reasons. White Mrs Collier must be repeated (her fragrance was the most intense), combined with some rich reds (maybe King Edward VII), and the deep purple heirloom variety Matucana. I’ve been searching the garden for a sunny spot where I can create a willow archway they can clamber up, and think I’ve come up with a plan. So watch this space.
Francesca Clarke, Journalist and Garden Designer
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