It’s really easy to sow and grow sweet pea seeds, and there’s a wealth of good advice available online if you need help – including videos, articles and social posts produced by some of the most knowledgeable garden bloggers in the UK. Whether you’re looking for germination tips, help with the cordon method or just some fresh inspiration, here’s everything you need to know about growing sweet peas.
- Best advice on how to grow sweet peas from seed
- Best advice on when to sow sweet peas – autumn or spring?
- Best advice on when to plant out sweet peas
- Best advice on the cordon method for growing sweet peas
- Best sweet pea varieties to try
Best advice on how to grow sweet peas from seed
Soaking your sweet pea seeds overnight before sowing is one of the many excellent tips from Adrienne of Wild About Gardening in her very informative article: Sow sweet peas for summer blooms. Once they’ve plumped up, she pops a seed or two in 8cm pots in a cold frame and covers them with newspaper until they germinate.
Elaine, one of The 3 Growbags sisters, celebrates the versatility of sweet peas and how simple they are to sow and grow – even for children – in her charming blog post: Lose yourself in plants. She sows her seeds as early as possible in root trainer pots indoors, but says you can even sow sweet pea seeds outdoors in warmer spring soils and still get good results.
If you’ve ever had problems getting your sweet pea seeds to germinate, Tony of Garden of Eaden has a generous little trick to share. Because the seeds of traditional varieties have a natural dormancy period, you need to nick the seed coat gently with a knife, rub it with sandpaper, or give the seeds a good soak. Check out his full post for more.
Geoff, aka The Biking Gardener, acknowledges that sweet peas need a bit more attention than other hardy annuals in his straight-talking article: Starting sweet peas. He wouldn’t be without them in the garden, though, and explains his different methods, starting with sowing seeds in a cold greenhouse. Full of wonderful little nuggets of wisdom as well as interesting facts.
Best advice on when to sow sweet peas – autumn or spring?
Late March is optimum sweet pea sowing time for enthusiast Alison of The Blackberry Garden, who grows them every year. She says that although autumn sowings haven’t worked out for her, an experiment sowing sweet peas in late January was very successful. It could be worth a try. And you’ll love her trip down memory lane – all inspired by a vintage sweet pea seed packet!
Instagram gardener Katrina, at Homegrown Garden, discovered the joy of growing sweet peas a couple of years ago and now she’s hooked, as her self-portrait with a freshly picked bunch of white and burgundy blooms illustrates beautifully. She has sown in spring before, but because she likes her displays to start as early in summer as possible, she’s resolved to sow sweet pea seeds in autumn from now on.
There’s no mistaking Alan of Down to Earth’s preference in his post: Sow Sweet Peas in Autumn. You can’t say it clearer than that! A former nursery owner, he says you definitely get the best sweet peas from an autumn sowing, but adds that late winter and early spring are next best – the more the merrier!
Sometimes a sweet pea obsession creeps up when you’re not expecting it, as Sarah of The Gardening Shoe reveals in her entertaining blog post: Sweet peas, Gin and the Perils of Gardening Clubs. Having picked up some top tips from a champion sweet pea grower, Sarah is now a confirmed October sower. For now, at least.
Best advice on how to plant out sweet peas
Tips for preparing the ground and practical advice on how to plant out your sweet peas is simply and brilliantly explained in this short video by Carol of The Sunday Gardener. In addition, her comprehensive sweet pea growing guide offers a good reminder that young sweet pea plants can go outside in spring – much earlier than most bedding plants – but only once the risk of frost is gone. Weather permitting, Carol gets hers out in April.
TV gardener David Domoney reminds us in his thorough and concise sowing and growing sweet peas instructions that indoor raised sweet pea seedlings should always be hardened off before you transplant them into the garden. That means putting the potted seedlings outside during the day and returning them under cover at night for a week or two.
Unless they’re tied or tumbling, sweet peas naturally look for something to cling to. In her chatty article, Sweet peas Part 1: Sowing and growing, Erika Packard explains how she uses jute netting, rather than canes, for her root-trainer-grown sweet pea seedlings to use as a climbing frame. Since coming to Britain from Virginia USA, horticulturist Erika has been thrilled to indulge her passion for sweet peas in a more amenable climate.
If you have limited space in the garden, flowering sweet peas look fantastic tumbling out of hanging baskets. Claire of Claire’s Allotment shows us how to achieve this in her no-nonsense, easy-to-follow video: Potting Out Sweet Peas. Claire hangs her sweet pea baskets by the back door to provide a waft of glorious scent each time she steps out. What a lovely idea!
The Cottage Smallholder, Fiona, suggests companion planting sweet peas with runner beans. Who isn’t tempted by the idea of returning from the kitchen garden with a bunch of each on a summer evening? Fiona explains that sweet peas and beans are both climbers and share the need for plenty of water and regular picking to stretch out their harvests, so it’s a win-win situation.
Best advice on the cordon method for growing sweet peas
The aim of growing your sweet peas by the cordon method is to achieve blooms with long straight stems for optimum flower arranging or showing potential. It can be labour intensive, but it’s all about quality over quantity.
If you want a sweet pea crop specifically for cutting and sitting nicely in a vase, look no further than Tea Break Gardener Katharine’s article on Growing sweet peas as cut flowers. Here you’ll find very detailed, beautifully illustrated instructions for creating a simple and effective cordon system. Having decided that 50 canes would be expensive to buy and difficult to store, Katharine’s clever step-by-step guide shows you how to use vertical strings to keep the cost down.
In an excellent video from Angela’s Kitchen Garden, host Angela shows you very clearly How to grow sweet peas with the cordon method – with close-up shots of exactly what to do. She reminds us of the importance of regularly snipping off the sweet pea plant tendrils to stop them wrapping around and damaging the flowers or twisting the stems as they climb up the canes.
If you’re the competitive type and intend to take your sweet peas to the show bench, then Tony the Gardener has plenty of insider tips and step-by-step photos to help you grow exhibition sweet peas. His article explains how he creates the perfect framework to support his plants and explains how to layer them when they reach the top of their canes.
There are more great tips in the Cotswold Posy Patch post Sweet peas – the cordon method. Liz and Laura grow their sweet peas in a polytunnel, using rows of 10ft canes to produce stunning, straight-stemmed sweet peas. When they reach the top of the cane, Liz lays the stem along the ground before training it up another one, five canes along. Take a look at the amazing photos of this intriguing method.
Best advice on sweet pea varieties to try
Everyone who grows sweet peas will discover one or two favourites – and there are certainly plenty to choose from. Here are some of the tried-and-tested varieties our bloggers recommend…
Over at Pumpkin Beth, horticulturist Beth takes her sweet pea growing very seriously and clearly gets a lot of pleasure from harvesting them. She has conducted a trio of exceptionally thorough sweet pea growing trials to explore the best time to sow sweet pea seeds, different growing methods, the best varieties, and how to produce the most blooms and the longest flower stems. Beth really knows her stuff and has done an extraordinary amount of work to share her excellent knowledge with fellow sweet pea lovers and gardeners.
There’s no doubting the passion allotment grower Bryony at Linnet Lane has for the scent and colour of sweet peas. Like her, you could choose to sow a sweet pea mix if you want blooms in a kaleidoscope of luscious colours this summer – from deep purples through Barbie pinks and creamy whites. She was delighted with the results from an old-fashioned mix but fell in love with this rather special salmony pink sweet pea specimen.
Adrienne at Wild About Gardening loves the old fashioned magenta and purple Cupani sweet pea for its heavenly scent, and recommends Spencer type, red white and blue Patriotic Mix from Suttons for both performance and perfume. (Image above.)
With all this excellent advice to follow there’s no reason why you can’t have a bumper crop of beautiful and fragrant sweet peas adorning your plot, scrambling over archways, climbing up frames, brightening up the patio and cascading from hanging baskets. What a wonderful thought!