Carnations in all their various forms are generally considered to be derivatives of Dianthus Caryophyllus, although the origin of some is not entirely clear. In North America, when referring to carnations, we immediately think of the carnation of commerce, the continuous or perpetual flowering carnation that is commonly grown under glass. There are, however, various garden types of this delightful flower that have never become so popular in North America as they are in many parts of Europe; this is because, over much of the continent, temperatures are too high for their successful, easy culture.
Carnations commonly grown by florists and gardeners in greenhouses are almost exclusively cultivated as cut flowers. They are essentially fall-to-spring bloomers and so supply blooms at a season when they are most highly valued.
They are started from cuttings, about 3 in. long, taken either from the base or bottom half of the stems of old plants. Cuttings made from shoots slightly above the base give the best results. Moderately strong cuttings produce heavy plants more quickly than do short or spindly ones. They can be rooted in about three weeks in a sand propagating bed in a temperature of 40 degrees. If the sand can be kept five degrees warmer than the air by using bottom heat, roots develop more quickly. Some growers use a hormone preparation on the cuttings before planting but this is unnecessary if the environment is conducive to root formation. December and January are the best months for inserting cuttings.
To prepare the cuttings, remove the leaves from the shoots for about % in. from their bases so that no leaves are buried in the sand. Make a clean cut across immediately below the lowest node of each cutting. Cut backRead more on backyardgardener.com