Dianthus, also known as Carnation or Sweet William and sometimes known as Pink, blooms heavily in the spring, on into the summer and if you deadhead them (remove the spent flowers after blooming) they are likely to bloom again even into the fall. They love full sun and do well in zones 4 through 9, but make sure you read the tag before purchasing them because each variety is a little different, especially regarding zone hardiness.
Dianthus is easy to care for, just plant them, water as needed, remove the spent flowers after they bloom and enjoy them. Come fall they take care of themselves.
Propagating Dianthus or Sweet William is really quite easy. The ideal time is June in most areas and May in warmer climates. You can take tip cuttings or remove a complete slip. A slip is kind of like an entire branch. These new growth shoots appear on the side of the plant, all around the plant just reach down and break one off. Chances are once you’ve removed this slip from the plant you can probably tear it into several smaller slips, leaving a little heel on the torn end. A heel is just a piece of frayed tissue from where you removed the slip from the plant.
In the rooting process plants tend to make new roots when and where they are wounded. Wounding is usually part of the propagation process. In most cases additional or intentional wounding isn’t necessary, especially when working with softwood cuttings.
A softwood cutting is a cutting that is taken during the growing season, usually about six weeks after the plants start growing in the spring. The new growth is soft and tender and roots easily. As the growing season progresses, plants start to prepare themselves for winter and the new growth hardens off, making the plant much more durable to stand up to the harsh winter conditions.
Once you take the slips off your Dianthus, remove all the leaves from about 1/2″ to 1″ of the bottom of the cutting and dip the cuttings in a rooting compound. It makes no difference whether you use a powder, a liquid or a gel. Stick the cuttings in a flat filled with a potting soil or seed starting mix that drains well and place the flat in the shade. Make sure the flat being used has holes in the bottom for drainage. Mist the cuttings as often as you can with a spray bottle.