Growing Sweet Peas for Cutting; Top Ten Tips

I have always loved sweet peas. I love their frilliness, their fragrance and their robust fragility. I love the whole ritual of growing them, and the pride in being able to cut bunches for vases indoors.

Part of the pleasure is that preparation of the ground and creating a support for these high maintenance, but hardy creatures that promise to be so rewarding, if you treat them well. Sweet peas are not difficult to grow but will punish you if you neglect them.

There is something nostalgic about sweet peas.  My mother always grew sweet peas and I remember the varieties to this day: ‘Leamington’, lavender blue, ‘Air Warden’, scarlet, ‘Elizabeth Taylor’, burgundy and ‘Mrs R. Bolton’, pink. Some of these are still around today, but such is the popularity of these wonderful summer flowers there are always new varieties and colour blends to choose from, also older Heritage varieties ascend once again into the realms of popularity. Scent is the quality, above all others, that ensures their success.

Take Sweet Pea 'Cupani' for example. Bred by a monk, Brother Cupani, back in 1699 its deep blue and purple flowers are wonderfully scented and it has become even more popular in recent years. The plant is not too large with delicate stems; ideal for growing up a willow obelisk in the border or even a large pot on the patio.

Dwarf trailing varieties of sweet pea have also become popular for patio pots and hanging baskets. These are really worthwhile summer bedding subjects, as long as you keep up with the watering feeding and dead-heading.

However for me personally Sweet peas are something I grow for cutting. They sit alongside the vegetable garden where I can keep an eye on them. I like to select individual varieties to give me a dreamy colour blend that always works, whichever plants are producing flowers. Within the Suttons Seeds range of Sweet peas I am spoilt for choice, whether I go for individual varieties, collections or colour blends.

My Top Ten Tips on growing Sweet Peas for cutting:

1. Prepare your ground

Ground preparation is paramount. Dig the soil deeply early in the year and add a good general base fertiliser. Organic matter and well-rotted manure is best added the previous autumn. If you mix in too much in the spring you may get lots of stems and leaves and few flowers.

2. Put up a good support.

Stout canes or hazel poles are ideal; they must give the plants a height of 2 metres (6ft) above ground to climb up. Your support must be strong and secure and allow the plants on both sides to get direct sunlight. Sweet peas do not grow well in shade.

3. Always sow sweet pea seeds in deep pots or tubes

They produce a long tap-root system which needs to develop if the plants are to grow successfully. Whatever you use make sure you can transplant without disturbing the roots. You can sow directly into the open ground from April onwards, however few have soil which gives the best results if grown in this way.

4. Planting out

As soon as seedlings are large enough (around 5cm, 2ins) in height, harden them off and plant them out; protect from slugs and snails and birds. Sweet peas are quite hardy and will grow better in the soil in cool conditions. Keeping them indoors for too long draws the plants and makes them weak.

5. Tying sweet peas

As the plants start to grow tie them into the canes or poles carefully using flexi-tie (that soft plastic tie), or soft string. You can also use the soft wire sweet pea rings. Be careful not to damage or break the stems.

6. Cutting back tendrils

Cutting off the tendrils is not essential, but it does prevent them from getting tangled up with their neighbours and the flower stems. Tendrils wrapped around flower stems result in bent and curly stems that are useless for cutting.

7. Watering is essential.

Dry soil at the roots during bud formation results in bud drop and stems without flowers. This usually happens at the beginning of the season when there is some rainfall and the grower assumes that the soil is wet enough; it often isn’t.

8. Keep cutting flowers

As the flowers open keep cutting; this stimulates further flower production. Never leave seeds to develop on the plants. Remember that sweet peas are annuals. If seeds develop they tell the plant that its work is done and the plant starts to die back.

9. Feed your sweet peas

As soon as the plants start to grow after planting out, and throughout the growing season, feed with a general liquid fertiliser. Tomato fertiliser or one formulated for summer bedding plants is ideal. Organic growers might like to try Dried Blood; that was my mother’s recipe for success and it always seemed to work.

10. Extend your sweet pea growing season

Remember that traditionally sweet peas were sown in the autumn outdoors in cold frames or in unheated greenhouses. This means that the plants are well developed and can be planted out early the following spring giving you earlier flowers. It’s worth growing half like this and half from a spring sowing to give you a longer season of flowers.

So which varieties will I be growing?

I was delighted to find 'Wiltshire Ripple' in the Suttons Seeds range. I saw this at Harlow Carr growing with the lovely deep burgundy 'Beaujolais'; glorious together. I also like the frilled and flecked mixture from Suttons Seeds, 'True Fragrance'.

I also love Sweet Pea 'Prince of Orange', another heirloom variety which I like in a contrasting combination with the rich purple-blue 'Cupani'. If you like the idea of these fragrant Heirloom varieties try Sweet Pea 'Juanita' a richly coloured mixture of some of the best of these highly scented flowers.

Finally for me it wouldn’t be sweet pea time without 'Noel Sutton'. This large flowered, frilled and fragrant, soft blue variety is the vision of the perfect Sweet Pea, it is just everything you expect from these wonderful flowers.

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