Seedlings started in the late Autumn or in January under glass will be ready to plant outside now or in the coming couple of weeks.
You’ll need to train tall varieties against canes, (just like runner beans) so buy a bundle of ten 2.4m (8 feet) bamboos and a securing ring or some ties to hold everything together. A lot of people like to stick some hazel sticks in the ground too so as the young plants have something to hold on to as they stretch ever upwards.
Find a sunny part of the garden and arrange your bamboos in a circle to make a wigwam shape or alternatively set them up 30cm (12 inches) apart in a straight double row.
If you don’t have any hazel, you may want to throw some pea and bean netting to the canes to form a continuous mesh; the plants tendrils will naturally cling to this, however, if you want to have the very best blooms and win your local garden show prizes, you will need to grow them up the bamboos as cordons, just as the exhibitors do.
Plant one sweet pea plant at the bottom of each cane.
Never grow the main shoot up the canes as they quickly run out of steam and become ‘blind’. Instead, tie in the strongest side-shoot from each plant to each cane and remove all the others. If there are no side-shoots, pinch out the growing tip to encourage them and then keep the best one for training,
As the stems grow, pinch out the side-shoots so as to direct all of the plants energy into the flowers and once they have formed, cut them regularly, not just for their sweet scent but because leaving them to set seed will stop them from forming.