Cut sweet pea flowers where the stem meets the vine. Bring them inside and place them in vases to enjoy their colorful blooms and fragrance. Do this throughout the season.
Cut off dead sweet pea flowers, called deadheading, at the base of the stem as soon as they wither. Toss the dead flower on the compost heap.
Do not let sweet pea flowers form seed heads. Cut them off as soon as you see them. As soon as the sweet pea vines start going to seed, they will start to die.