Once the hard frosts are done — a fortnight either side of April here. Start a few in deep pots on a cold sill in March if you can’t wait, but keep them cool and hungry: pamper a sweet pea and she sulks.
Two full inches. Deeper than looks right. Sow her shy at an inch and she flops about all summer with no proper root under her.
Six inches between plants along the cane row, one plant to a cane, canes a hand-span apart. Crowd them and you’ll be fighting mildew the whole of July.
NICK EVERY SEED first. A little cut with the knife-tip on the fat round side, clear of the pale eye — then soak them overnight in a saucer of water till they swell. Skip it and half of ’em never wake up. That hard black coat is the whole trouble; the knife is the whole answer.
PINCH THEM OUT at four leaves. Nip the growing tip clean off with your finger and thumb — I don’t care how it hurts, do it, or you’ll get one weedy string and no flowers. Pinched, she throws four strong shoots from the base instead.
She will not climb string on her own — she hasn’t the sense. Twist the whippy new growth onto the canes yourself, a turn every few days, and tie the leaders soft.
And CUT HER. Keep cutting armfuls every second day, more than you can use, whether you want the flowers indoors or not. Let one pod set and swell and she reckons the job’s done and quits on you for the season. The pod is the enemy. Cut, cut, cut — right up to the frosts.