How to Grow Sweet Peas: Why I Sow Them in Autumn

Discover why I sow sweet peas in autumn, how I save my own seeds and why these beautifully scented flowers are a favourite for cutting gardens and wedding bouquets.

If I had to choose just one flower for my cutting garden, it would probably be the sweet pea.

I love everything about them: the colour, the scent, the delicate, slightly crumpled petals and the way they seem to tumble and dance rather than sit politely in a vase. They feel quintessentially English and, for me, they are one of the flowers that really signal the arrival of summer.

And then there are the tendrils.

I absolutely love using the long, curling tendrils of sweet peas in big, abundant arrangements. They have a lovely wildness to them, winding their way through other flowers and foliage and giving an arrangement movement. When I’m making a really generous, just-gathered-from-the-garden design, those little tendrils can be the thing that makes it feel completely natural.

They are also wonderful flowers for weddings. Sweet peas work beautifully in bridal bouquets and bridesmaids’ flowers, particularly if you’re looking for something romantic, seasonal and a little bit informal. They bring scent as well as colour, which makes a bouquet feel extra special.

Why I sow sweet peas in autumn

I sow my sweet peas in autumn rather than waiting until spring. It does mean looking after them through the winter, but I think the reward is worth it.

Autumn-sown sweet peas have the opportunity to establish a good, strong root system before winter really sets in. Once spring arrives, they are ready to get going, producing strong, tall plants and, generally, earlier flowers than those sown over winter.

And if you grow sweet peas for cutting, earlier flowers are very welcome indeed.

I sow mine in deep pots or root trainers because sweet peas like to make plenty of roots. I keep the young plants somewhere sheltered and protect them from the worst of the winter weather before planting them out in spring, once they are strong enough.

Saving my own sweet pea seeds

At the end of every season, I leave some of my sweet pea flowers on the plants rather than picking them for the vase. Eventually the pods swell, dry and turn brown, and that’s when I collect the seeds.

There is a slight element of garden roulette when you save your own seed. Sweet peas cross-pollinate, so unless you have been carefully isolating individual varieties, you can never be completely sure what colour or combination will appear the following year.

But I rather like that.

There’s something lovely about planting a handful of seeds you collected yourself and waiting to see what emerges. Perhaps it will be a favourite soft pink. Perhaps a deep purple. Perhaps something I’ve never grown before.

After a long, cold winter, I’m really not going to complain about whichever colour decides to grace my cutting garden.

Sweet peas in the cutting garden

Sweet peas are wonderfully generous flowers. Give them a sunny spot, something sturdy to climb and keep picking the flowers regularly, and they will reward you with armfuls of blooms.

And don't overlook the tendrils. When I’m creating larger arrangements, I love allowing the long, curling stems to trail and weave through the other flowers. They soften the edges of an arrangement and give it that lovely, slightly untamed feeling that you get when you gather flowers straight from the garden.

For weddings, sweet peas are particularly special. Their soft, romantic flowers and beautiful scent make them perfect for bridal bouquets and bridesmaids’ bouquets, whether they are used on their own or mixed with other seasonal flowers.

Why I’ll keep growing them

Sweet peas aren't precious. They don't need to be perfect. In fact, I think they are at their most beautiful when they are slightly wild and unruly, with a few tendrils curling around the stems and flowers tumbling in every direction.

For me, they are the perfect cutting garden flower: easy to grow, beautifully scented, wonderfully generous and endlessly useful in a vase.

And come late summer next year, I’ll be back in the garden collecting those little brown seed pods, ready to do it all over again.