Sweet perfection

AT last we have reached the time of year when sweet peas we have grown from seed over the past few months perched on windowsills and in our greenhouses can be hardened off and planted out.

A few years ago when I was a student in the garden at RHS Harlow Carr, as part of my traineeship I had to design, build and tend an allotment plot for the year. As part of this I decided to grow the red sweet pea Winston Churchill in the cordon method. This is usually used by exhibitors or those wanting to grow excellent quality sweet pea stems.

There are so many ways to support sweet peas, with pea sticks, on wigwams made from hazel sticks or bamboo canes, scrambling up chicken wire or through pea netting. As long as there is something for the sweet pea tendrils to cling to they will climb well.

The cordon method was something I had always wanted to try since hearing about it at college, the method promised fewer but taller, straighter stems and better blooms. Although time consuming it is definitely worth a go, I grew eight plants and it kept me in beautiful, long stemmed sweet peas for the season.

You support the sweet peas using the classic ‘A-frame’ used for climbing beans using bamboo canes or hazel poles. Space the rows 30cm apart and each pole a foot, 30cm apart. The soil is best prepared by digging over the area and adding well-rotted manure or garden compost. If drainage is poor also add horticultural grit.

Plant one hardened off sweet pea at the foot of each pole. Let them settle for 4-6 weeks. At this point reduce each plants growth to a single shoot by nipping out or removing other stems. Tie these in loosely to the pole with sting or a loop of wire. Remove any side shoots where the leaves join the stem, the leaf axial, and any tendrils you see. Continue to tie in the main stem as it grows up the support.

It is important to pick the blooms regularly. The aim is to concentrate the energy used by the plant to form a smaller number of blooms, but with a much higher quality in both stem length and number of flowers per stem. Feed weekly with a high potash fertiliser, such as a weak tomato feed.

The concentrated growth means the plants will quickly reach the top of the growing frame before the end of the season. The plants will need to be layered. Untie each individual stem, carefully as they will be brittle and lay the horizontally around the base of the frame. As the shoots continue to grow the can be tied onto the canes beginning the process again.

Growing sweet peas in this traditional method does take time, tending little and often the best way, but as the sunny evenings roll in it’s a lovely job to take on. So if you have a spare few plants why not have a go. Displays of sweet peas can be seen in the productive garden at Harlow Carr.

Jobs to do

Deadhead daffodil and tulip bulbs to producing better blooms for next year.

Create supports for herbaceous perennials before they get too large.

Regularly hoe off weeds in beds, it will pay dividends when the borders are in full swing.

Tie in climbing and rambling roses.

Sow hardy annuals such as sunflowers for summer displays.

For more information on things to do in the garden this month visit rhs.org.uk

DIARY DATES

April 30 to May 1: Spring Plant Festival

Celebrate the best of spring gardening at the Spring Plant Festival in conjunction with Plant Heritage. Specialist nurseries will sell a range of beautiful plants. This hugely popular event will provide inspiration for your own garden and a wealth of advice and information alongside the RHS Tulip and Daffodil competition.

May 1 to 29: Bath House Gallery – Art & Photography Showcase

Whether you like traditional oils and watercolours or modern photography, there will be a wide choice of styles to choose from including work by regulars such as Teresa Boast and Nikky Corker alongside artists exhibiting for the first time.