Beautiful and easy to grow, carnations are an herbaceous perennial plant that is a popular choice for flower gardens, rock gardens and cut flowers. With long green stems and blooms in pink, purple, red, white and yellow, carnations are an attractive addition to any bouquet or landscape. A hardy flower variety, carnations are the perfect garden project, whether you are a beginning gardener or a gardening pro. Not a fussy flower, carnations can be grown in just about any climate.
In 1990, the United States Department of Agriculture (USDA) released an updated version of its USDA Plant Hardiness Zone Map. The USDA compiled and analyzed 10 years worth of temperature data from around the country and used each region's lowest average annual temperature to assign it to a zone. The zones of the USDA Plant Hardiness Zone Map are used to help consumers know which plants will grow best in their areas.
Carnations can be grown in USDA hardiness zones three to 10, depending on which of the 300 varieties of carnations you are growing. Desmond carnations, for instance, can be grown in USDA hardiness zones four through eight, while Hardy Mixed Carnations thrive in zones three to nine. Not a cold hardy flower, carnations may be prematurely lost to cold weather when planted in zone three.
The average annual minimum temperature recorded for zone three is between negative 30 and negative 35 degrees below zero F, while the average annual minimum temperature for zone eight is between 15 and 20 degrees F. This gives an idea of the range of temperatures that carnations can tolerate. The ideal daytime temperature for growing carnations is between 50 and 59 degrees F. The ideal night time temperature for growing carnations is between 41 and 46 degrees F.
Carnations do best when grown in a location that receives at least five hours of full sun per day. For best results, carnations should be planted in well drained soil that is slightly alkaline. Fertilize carnations regularly with a commercial fertilizer or organic materials, such as peat or pulverized pine bark. Water carnations sparingly, except in the summer months. Do not allow the soil to become too moist to avoid the risk of root rot. Prune carnations periodically to keep them healthy and increase the air flow around the flowers. Regular trimming will increase the growth of the carnations and reduce their risk of disease.