Many species exist in the Dianthus genus of flowering plants. They have many common names, including sweet william, pinks and carnations. Many Dianthus plants sport fragrant flowers in shades of pink, red, lavender or two-tone blooms that are attractive in floral arrangements. Dianthus plants of all species are relatively easy to grow from seed, or you can purchase bedding plants at a garden supply centre. During their summer blooming season, pruning off spent flowers can increase flowering and extend the blooming season.
Cut flower stalks back to the main stem, above a set of leaves, soon after the flowers open in late spring or early summer. Use regular household scissors for small stalks and garden clippers for thicker stalks. Discard any wilted or dead flowers and use fresh flowers for floral arrangements.
Snip off individual flowers after they begin to drop their petals and wilt. Use your fingertips or scissors for this task. If you keep up with pruning, you will prevent the plant from forming seeds, so it will continue to produce more flowers instead.
Water Dianthus plants thoroughly to soak the soil after you cut back flowers and foliage.
Gather your dead Dianthus flowers and yellow or unhealthy foliage in a basket. Cut the foliage and flowers you have pruned into 2-inch-long pieces and then add them to your compost pile.
Allow some flowers to remain on plants in late summer if you want to collect seeds for next year's plants. Many species of Dianthus will drop their seeds to the ground and resow themselves naturally, making your gardening duties easier the following year.
Put cut flowers intended for a floral display into water as soon as possible after you prune your Dianthus plants.
Don't overdo it when you prune Dianthus: the plant can suffer if you cut off more than about one third of its volume, including both flowers and foliage. Avoid cutting off an excessive number of leaves and foliage from Dianthus plants, because the plant needs them for successful photosynthesis.