Sweet Peas are an excellent early cut flower to grow and they thrive if you have a polytunnel. They are also very hardy and very easy to grow. They produce a good crop of long stemmed and sweet smelling flowers, whilst taking up only a small area of ground.
Fill the cells of the Rootrainer tray with good multi-purpose compost and wet it thoroughly then sow one seed into each cell about 2cm deep. If you are using the Rowplanter, place the seeds 15cm apart.
If you have a heated propagator then place the tray into it or else cover the tray with the propagating lid and leave until the first seeds emerge.
At this stage the trays should be transferred to a bench in the polytunnel (if you have one), or they can be left in the greenhouse to slowly grow on. When the plants have three leaves, pinch out the tops so that the resulting side shoots become stronger and more vigorous than the main stem.
In February/March they can be planted out in the polytunnel in double rows with the plants spaced 15cm apart. If you are using the Rowplanter, you will simply need to slide the rows into the prepared trenches.
It will then be necessary to fix a vertical net to allow the plants to climb or alternatively to tie each plant to its own cane with sweet pea rings.
All that is then needed is to water well and harvest the blooms regularly, not leaving any to form pods.
As soon as the blooms become short stemmed, pull up the plants and replace with the summer crop.
Remember that you can leave the plants in Rootrainers until the weather is warm enough to plant outside.