Carnations can seem so familiar that some gardeners overlook them entirely. However, this distinctive ruffled bloom is essential to cultures all over the world: from Mother’s Day and weddings to religious and political traditions. Their official name, Dianthus, roughly translates from ancient Greek as "divine flower," and the common name — carnation — is thought to come from the Latin word for crown.
These perennial plants are thought to be native to the Mediterranean, where they are often found growing wild. Traditional varieties have a sweet smell of cloves. Flowers in the Dianthus family are generally easy and rewarding to grow and available in a wide range of colors.
Generally, it’s best to plant carnation seeds indoors around 6 to 8 weeks before the last frost. Choose well-drained, slightly alkaline soil, sow the seeds thinly and sprinkle a thin layer of soil on top.
Dampen the earth with a spray bottle but don’t overwater the seeds. Place them somewhere with plenty of indirect sunlight, under a plastic bottle or bag to help with germination. When the risk of very cold weather has passed and the seedlings reach around four inches in height, it’s time to plant them outside.
Many carnations will reach between 18 and 24 inches in height, with flowers around two to three inches in diameter, so the young plants should be spaced 6 to 12 inches apart when planting out, depending on the variety. These plants work equally well in large outdoor containers and along sunny borders.
Carnations prefer full sun but will tolerate partial shade. USDA hardiness zones 3 to 10 can all be suitable, depending on the variety you choose, but the most traditional varieties of Dianthus will thrive in less humid areas of zones 7 to 10. These areas are warm without being overly arid, similar to their natural Mediterranean habitat.
Watering your carnations once per week, either in the early mornings or evenings, should be enough to help young plants establish themselves in all but the hottest weather. If temperatures rise dramatically and the soil starts to feel very dry you could increase this to two to three times each week.
Avoid overwatering them or getting the plants themselves wet, as this can cause the leaves to turn yellow and rot. Instead, only water the soil around the plants.
Although carnations are generally straightforward to grow, there are plenty of bugs that love them as much as humans do. Common pests include red spider mites, aphids, and thrips.
As carnations don’t enjoy being hosed down, try encouraging natural predators like ladybugs and birds into your garden to keep pests under control.
Carnations can be prone to bacterial leaf spot, crown gall, bacterial wilt, and rust. To help stop the disease from spreading, cut off any affected leaves and dispose of them away from your garden, then monitor the situation closely. Caring for your plants regularly and keeping a close eye on them will give you the best chance of spotting any diseases early.
Taller varieties may need extra support as the flowers grow. Deadhead spent flowers regularly to promote further blooming. If you live somewhere with particularly hot summers, you might want to think about rigging up a temporary shade for your carnations during the warmest part of the day to prevent them from being scorched.
Apply a general flower fertilizer containing phosphorous, nitrogen, and potassium every couple of months.
In early to mid-summer, take cuttings by pulling off small side shoots. Remove the very lowest leaves from each cutting, dip the stems into hormone rooting powder, then firm them into some general potting compost. Water your cuttings moderately and firm them in again if needed.
Leave them somewhere warm and sheltered but away from direct sun, and mist them with water every couple of days depending on the weather. Remove your new carnation plants from the shelter after 4 weeks and allow them to harden off. After a further two weeks, they should be ready to plant out.
Carnations have a long history of being used to relieve stress, inflammation, and certain skin conditions through massage, aromatherapy, and brewing as a traditional tea.
As beautiful as ornate "double" flowers are, they’re not much help to bees looking for nectar. Choose "single" flowering varieties, particularly those with a strong scent, to attract beneficial insects into your outdoor space.
The Dianthus family includes hundreds of different species. They can be divided into three basic types: large, spray, and dwarf.