Dianthus caryophyllus Seeds | Carnation
LATIN NAME: Dianthus caryophyllus
COMMON NAME: Carnation
Plant Profile
The petal edges are cut into a fine fringe, the mark that separates carnation from the smoother-petalled pinks. The stem is slender and jointed, swelling at the nodes, and the flowers are carried singly or in small clusters at the tip. The colour range spans pink, red, white, yellow, and bicolours bred for the trade.
The leaves are narrow and linear, a distinct grey-green, and the waxy bloom on the stem and leaf gives the whole plant a slightly blue-grey cast. That cool tone is why carnations read as blue-grey even in hot colours, and it sets them apart from the brighter greens of most cut flowers.
The petal colour comes from anthocyanin pigments, with the exact hue set by pH and by co-pigments in the cell. Red and pink carnations are anthocyanin-driven, while white forms lack the pigment. Breeders have also produced green and purple-edged novelties by juggling the same pigment pathways. The pigment work is well enough understood that breeders can hold a colour line across generations by selecting parent clones.
The carnation is the tall, clove-scented member of a large genus that also gives us the low border pinks. Close relatives such as Dianthus plumarius and Dianthus chinensis share the fringed petal and the spicy scent but stay low and are grown for the rock garden and the front row rather than the vase.
The garden pinks descended from species like the carnation and were selected for a compact mound and a long bloom at the front of the border. They carry the same eugenol scent in lighter measure, so the cottage pink is, in a sense, the carnation brought down to size.
Science & Biotechnology
The clove scent is carried chiefly by eugenol, the same phenylpropene that dominates clove oil, along with smaller amounts of related volatiles. The compound is what the perfume industry captures as carnation absolute, used to build spicy, floral notes in fine fragrance. Breeding for a stronger or weaker scent is really breeding for more or less eugenol in the petal tissue.
Uses & Benefits
The carnation’s scent is the reason for its name. The Greek word karyophyllon means “nut leaf,” a reference to the clove, and the flower smells exactly of clove because it shares the same signature compound, eugenol. For centuries the carnation was the cut flower of choice for perfumers and painters alike, and its fringed petals appear in more still-life paintings than almost any other bloom. Carnations have been cultivated around the Mediterranean since the start of written garden history and turn up in frescoes from ancient Rome. What is less known is that the perfume and flavour industries still distil the clove note from carnation absolute, so the garden flower and the scent bottle are the same plant.
Carnation absolute is valued for its warm, spicy character with a clove-like note that rounds out floral compositions. Though synthetic eugenol exists, the natural absolute from the flower keeps a place in high-end perfumery, linking the cutting bench directly to the perfume flask.
Pinch the young plant once to force side shoots, which gives several stems instead of one and improves the cut-flower yield. Feed through the season and support the stems as they rise. Cut the blooms when the first petal loosens from the calyx for the longest vase life.
Growing from Seed
Sow the fine seed on a moist, free-draining medium and keep it warm and bright; the seed needs light and should sit on the surface. Carnations are slow to make a stem, so start them early and grow the young plants on in cool, airy conditions. Set them out in deep, well-drained ground with an alkaline lean for the straightest cutting stems.
Press the seed to the surface and mist to settle, then keep the medium just moist and bright. The seedlings are small and prone to damping off, so give them air and avoid wet feet. Prick them out as soon as they can be handled and move them to individual pots to build a strong root ball.
Our Take
Carnation is the cut flower with a spice-cabinet scent, and it rewards a patient hand. Sow early, pinch once, and keep the air moving to beat disease. For more in the genus, see Dianthus superbus, Sweet William, and Dianthus plumarius.
Related Reading
More species in the same orbit as Carnation: