About this variety
These are the Spencer sweet peas, bred for the show bench rather than the kitchen table. Large frilled flowers, four to a stem, on stems long and straight enough to be laid out for judging.
Getting that stem length means growing them as cordons: one stem per plant tied to a cane, all sideshoots and tendrils removed as they appear, everything fed into a single strong lead. It is more work than letting them scramble, and it is the only way to reach exhibition length.
Autumn sowing gives the strongest plants. Feed weekly once flowering starts, never let them dry out, and pick every two or three days. If you are growing for the house rather than the bench, let them climb naturally and they will still be excellent.