Growing sweet peas from seed

by Adam Pasco

Brighter days and lighter evenings are really cheering me up, as is the anticipation of borders packed with sunflowers and sweet peas this summer.

Adam Pasco picking sweet peasBrighter days and lighter evenings are really cheering me up, as is the anticipation of borders packed with sunflowers and sweet peas this summer.

Seeds from the free packet of sunflower 'Russian Giant' and sweet pea '20th Anniversary Mix' that came with the April issue of Gardeners' World magazine have now been sown, and seedlings have germinated. This is one gardening activity that never fails to give me a thrill.

There was a time when advice for sowing sweet peas did become quite demanding. It was claimed that the thick seed coats of sweet peas needed chipping with a knife or sanding down to allow water to enter the seed. Times have changed, and so has the advice. Just soaking sweet pea seeds in a glass of water overnight is all that's required, and seeds should soon germinate.

I do prefer sowing in small pots in my greenhouse, and then planting out seedlings, but if you really don't want the hassle just sow them directly into the soil in May at the base of a support. Once shoots have grown about 15cm tall, and carry several leaves, pinch out the tip. This encourage two or three side shoots to develop lower down the stems, and each of these can be trained up to carry flowers.

However, if it's really large stems of sweet peas for cut flowers that you're after, then leave the main shoot to grow and remove any side shoots. Let each plant concentrate on forming a single stem and the resulting flowers should be bigger. You'll get less of them, but these long-stemmed fragrant flowers will look perfect in a vase.

Some say sunflowers form better plants if sown outside where you want them to flower, as transplanting seedlings stunts their growth. I'm hedging my bets, and have sown some in pots to be planted out in early May to join seeds sown directly in the ground. It will be interesting to see which ones grow best.

I know Kate Bradbury, my fellow blogger, likes to think she's in with a chance to grow a taller sunflower than David Hurrion and me, but I'm feeling confident mine will top hers. That's not to say expect to beat the Guinness World Record of 8.03m (that's over 26ft in old money), but who knows?

With thousands of Gardeners' World magazine readers now sowing their free sunflower seeds too I think we'll all have some stiff competition...

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Gardeners' World Web User 04/04/2011 at 14:53

My sweet peas have been sown two differnt ways soaking over night and just sowing straight into compost filled toilet tubes. The soaked ones grew leggy but the other ones grew ok. They were both put in the same window sill to grow but are still growing ok.

Gardeners' World Web User 04/04/2011 at 16:50

Is it ok to transplant autumn sown sweet peas outside now?

Gardeners' World Web User 04/04/2011 at 21:56

Reply to clematis: Yes, if the weather forecast remains good then I'd plant them out at the base of some support that they can climb up. Do water regularly after planting if the weather stays dry. Hasn't it been a dry March – well, it has been in the east Midlands. And 'green fingers'– interesting observation. I'll have to do the same trial and compare to see if I get the same results.

Gardeners' World Web User 05/04/2011 at 09:33

I sowed some sweet peas in loo roll tubes a few weeks ago & put them on the kitchen widowsill. Some of the seeds have germinated, most have not. Have never soaked sweetpea seeds overnight & usually sow them into pots & have never had any trouble with them germinating. Infact I always end up with too many plants & give loads to my neighbour. Sowed some more on Friday into loo roll holders & some in to pots. Did soak these seeds overnight so will be interesting to see what happens. Sowed 4 of my Russian Giant seeds in to pots on Thursday. Will sow a few more next week. I've never grown giant sunflowers before as I only have a tiny garden so I usually grow the smaller versions. I'm really looking forward to my giants(If they grow that big, of course):)

Gardeners' World Web User 05/04/2011 at 12:55

Ive grown my sweet peas in loo rolls and they have all grown really well, i did the same last year and had a really good show of sweet peas. Ive sown some of my Russian Giant seeds today, never grown the giant ones before, so here's hoping for a big one.

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