Cheddar pinks (Dianthus)

Dianthus plants are also known as Carnations, Sweet William and Pinks, and are often a staple in flower gardens. The family of plants are characterized by the spicy fragrance of their pretty blooms, often compared to cinnamon and cloves.

I. Appearance and Characteristics 

Dianthus ( dy-AN-thəs) is a genus of about 340 species of flowering plants in the family Caryophyllaceae, native mainly to Europe and Asia, with a few species in north Africa and in southern Africa, and one species (D. repens) in arctic North America. Common names include carnation (D. caryophyllus), pink (D. plumarius and related species) and sweet william (D. barbatus).

The species are mostly herbaceous perennials, a few are annual or biennial, and some are low subshrubs with woody basil stems. The leaves are opposite, simple, mostly linear and often strongly glaucous grey green to blue green. The flowers have five petals, typically with a frilled or pinked margin, and are (in almost all species) pale to dark pink. One species, D. knappii, has yellow flowers with a purple centre. Some species, particularly the perennial pinks, are noted for their strong spicy fragrance.

Dianthus species are used as food plants by the larvae of some Lepidoptera species including cabbage moth, double-striped pug, large yellow underwing and the lychnis. Also three species of Coleophora case-bearers feed exclusively on Dianthus; C. dianthi, C. dianthivora and C. musculella (which feeds exclusively on D. superbus).

II. How to Grow and Care

Sunlight

Full sun—at least six hours per day—is ideal for dianthus, but it will also tolerate partial shade. Although the type commonly known as carnations dislikes heat, the flowers still need ample sunlight to help them stand tall. This can make them a poor candidate for southern gardens.

Temperature and Humidity

These cool-season plants, ideally planted in spring and fall, can withstand a light frost. However, dianthus may begin to exhibit signs of stress below about 40°F. Most varieties won’t thrive in hot, humid conditions and stop blooming once the temperature rises in summer.

Watering

Dianthus flowers need weekly watering. Aim to give plants 1 inch of water per week, but avoid water-logging the soil.

Soil

Stem rot can be a problem in dianthus plants if their soil doesn’t drain well. If the soil in your garden is heavy clay, consider containers or raised beds for your plants instead. Additionally, dianthus plants like a neutral to slightly alkaline soil pH. If your soil pH is below 7.0, correct the acidity with an application of dolomitic limestone (fireplace ashes can also increase soil alkalinity). It’s fine to use mulch to keep weeds under control but avoid letting the mulch crowd around the crowns of dianthus to avoid rot.

Fertilizing

Dianthus plants are light feeders and won’t need much in the way of traditional fertilizer. A shovelful of compost worked into the soil once a year is enough to nourish the plants.

Planting Instructions

The cooler months of spring and fall are the ideal time for planting. Space dianthus about 6 to 18 inches apart, depending on the type; dig a hole roughly twice the size of the root ball. If you spread mulch, opt for a thin layer, since air circulation is essential to the health of the stem.

Pruning

Dianthus plants come in all shapes and sizes, so pruning needs will vary. Miniature varieties form a tight little lump of foliage and blooms, while giant species have almost no basal foliage. Mat-forming perennial varieties feature very tight-knit spreads of foliage, and as they grow, you may notice dead spots in the center of the foliage. When this occurs, divide the plant and replant it to encourage new growth. Remove any old, dead foliage throughout the season.

Removing old blossoms on all types of dianthus encourages another round of blooming. Make sure you know whether the plant is a true perennial or a biennial before you start deadheading. For biennial varieties, blooming is a sign they’ve reached their final year. But if you leave some of the spent flowers on the plant, they will seed your garden to produce plants next year.

At the end of the season, you can leave the foliage of your dianthus behind for winter interest. Alternatively, trim the plants back, leaving 1 to 2 inches above the soil line.

Propagation

Stem cuttings

While dianthus plants are more readily started from seed, they can also be propagated using stem cuttings, which will assure that the new plants will have the same characteristics as the “mother plant.” To propagate, follow these steps:

• Take a 2 to 3 inch cutting from an established mother plant that has bloomed for at least a full season. Cuttings should be taken in June or July after the plant has bloomed for the season.
• In a small pot, combine potting soil with vermiculite—the mixture should be moist but not damp or soggy.
• Dip the cut end of the cutting in a rooting hormone.
• Plant the cutting into the potting soil, ensuring that at least one node falls beneath the soil line.
• Place the pot in a warm, sunny location.
• Keep the soil moist—the cutting should take root within a month or so.
• Once you spot new leaf growth, you can transplant the cutting and care for it as normal.

Seed

Dianthus plants are easy to grow from seed, but there is no guarantee that the plants that result will mirror that of the “parent” blooms. To grow from seed, plant into a seed tray indoors around 8 weeks before the final frost in your area. Keep the seed tray somewhere warm and sunny until the seedlings germinate, which should happen in approximately eight to 10 days.

Continue to grow the seedlings indoors until they’ve reached 4 inches tall. They can be then planted outdoors once all risk of frost has passed.

Pests and Diseases

One of the biggest issues dianthus plants have is vascular wilt. Characterized by dull green stems that droop and eventually dry out, wilt is technically a fungus that can eventually kill an entire plant. Treatment is difficult as fungicides are not effective—therefore, it’s important to rotate your plantings frequently and avoid planting in any soil that seems diseased.2

Additionally, dianthus plants may have issues with other common plant pests, such as spider mites and aphids. To treat, you can apply insecticidal soap or neem oil until all signs of an infestation are gone.

III. How to Get Perennial Dianthus to Bloom

Lucky for many gardeners, dianthus plants are easy to care for and rarely have trouble blooming. Still, if you’re having trouble getting your plants to show off, there are a few things to keep in mind. First and foremost, dianthus plants should be located somewhere that gets at least six hours of bright sunlight daily. Too little light can impact the frequency and vibrancy of the blooms.

Additionally, ample water is important for the overall health and blooming of dianthus plants. Ensure that the soil doesn’t get dried out with frequent weekly watering—you can also mulch over the soil around the roots of the plant to lock in moisture and prevent evaporation.

Finally, proper grooming is essential to encouraging dianthus plants to bloom. By frequently deadheading the spent blooms, you’ll invite the plant to produce more buds and foliage, rather than putting energy into turning the spent flowers into seed.

IV. Dianthus Companion Plants

Geranium

One of the longest bloomers in the garden, the hardy geranium bears little flowers for months at a time. The jewel-tone, saucer-shape blossoms sit above mounds of handsome lobed foliage. Tough and reliable, geraniums need full sun and can thrive in a wide range of soils. Many of the best varieties are hybrids.

Coralbells

Exciting new varieties with incredible foliage patterns have put coralbells (Heuchera) on the map. Though they used to be sought out only for their spires of dainty reddish flowers, coralbells are now also beloved for the unusual mottling and veining of their leaves. The low clumps of long-stemmed evergreen or semi-evergreen lobed foliage make coralbells excellent groundcover plants. They enjoy humus-rich, moisture-retaining soil.

Iris

Irises, named for the Greek goddess of the rainbow, come in multiple colors and many heights. Whatever hue or size, all irises feature intricate flowers consisting of three upright “standard” petals and three drooping “fall” petals, often in different colors. Some cultivars show off with a second bloom in late summer.

V. Uses and Benefits 

Dianthus flowers, with their captivating charm and delicate beauty, have found diverse uses beyond simply adorning gardens. From cultural traditions to culinary delights, these blossoms have a range of applications that showcase their versatility. Here are some of the notable uses of Dianthus flowers.

• Ornamental Uses

The primary use of Dianthus flowers is as ornamental plants. Their vibrant colors, intricate patterns, and sweet fragrance make them a popular choice for gardens, borders, containers, and hanging baskets. Whether planted en masse or used as accent plants, Dianthus flowers add a touch of elegance and splendor to any landscape.

• Cut Flowers and Floral Arrangements

Dianthus flowers are highly valued for their long vase life and lasting beauty. Their sturdy stems and vibrant blooms make them ideal for cut flower arrangements. Whether used as focal flowers or filler blooms, Dianthus flowers bring color, texture, and fragrance to bouquets and floral displays, adding a touch of sophistication to special occasions and everyday arrangements.

• Culinary Delights

Certain species of Dianthus flowers are edible and used in culinary preparations. The petals of Dianthus caryophyllus, commonly known as carnations, have a mild, clove-like flavor and are used to garnish salads, desserts, and drinks. They can also be candied or used to infuse syrups and liqueurs, adding a unique and fragrant twist to culinary creations.

• Medicinal and Herbal Remedies

In traditional medicine, Dianthus flowers have been used for their potential health benefits. Various parts of the plant, including the flowers, leaves, and stems, are believed to possess anti-inflammatory, antifungal, and antibacterial properties. Infusions or extracts made from Dianthus flowers have been used to soothe digestive issues, relieve respiratory ailments, and promote overall well-being.

• Symbolic and Cultural Significance

Dianthus flowers hold symbolic meanings that have transcended cultures and traditions. Throughout history, they have been associated with love, fascination, distinction, and motherly love. In many societies, Dianthus flowers are used to celebrate occasions like weddings, anniversaries, and religious ceremonies, symbolizing joy, purity, and divine presence.

• Perfumery and Aromatherapy

The delightful fragrance of Dianthus flowers has made them a valued ingredient in the world of perfumery and aromatherapy. The essential oils extracted from Dianthus flowers are used in perfumes, scented candles, potpourris, and bath products. The sweet, spicy scent of Dianthus flowers is known for its calming and mood-enhancing properties, making it a favorite in aromatherapy practices.

• Natural Dyes

The petals of certain Dianthus flowers can be used to create natural dyes. They yield soft, pastel shades, which can be used to color fabrics, yarns, and other materials. This natural dyeing process adds an eco-friendly and unique touch to textile arts and crafts.

The uses of Dianthus flowers extend far beyond their visual appeal, as they find their way into various aspects of human life. From decorative purposes to culinary and therapeutic applications, these versatile blossoms continue to inspire and enhance our experiences, connecting us with nature’s beauty and cultural traditions.